TEACHER’S RESOURCE BOOK Natural Science 4 is a collective work, conceived, designed and created by the Primary Education department at Santillana, under the supervision of Teresa Grence Ruiz. WRITER Belén Garrido MANAGING EDITOR Sheila Tourle PROJECT EDITOR Geona Edwards EDITOR Beatriz García Hipólito PROOFREADING Saffron Frankland James Price PRIMARY Natural Science Contents Nombre Fecha Introduction ...................................................................................................... III Worksheets Life processes .................................................................................................... 6 Your senses ........................................................................................................ 14 The circulatory system ........................................................................................ 22 Respiration and excretion ................................................................................... 30 Reproduction ...................................................................................................... 38 People and health ............................................................................................... 46 Classifying living things ....................................................................................... 54 Animals .............................................................................................................. 62 Plants ................................................................................................................. 70 Wild plants and crops ......................................................................................... 78 Matter and materials ........................................................................................... 86 Forces and energy .............................................................................................. 94 Forces and movement ........................................................................................ 102 Heat and light ..................................................................................................... 110 Machines ............................................................................................................ 118 Introduction Natural Science 4 Teacher’s Resource Book provides a wide variety of photocopiable worksheets designed to complement Natural Science 4 Student’s Book and Natural Science 4 Teacher’s Book. It is divided into 15 topics in order to cover the main concepts of both the National Curriculum and the curriculum established by the Community of Madrid. These worksheets facilitate a flexible approach in the classroom. Students in the same class can be given different worksheets. They can expand on the material learnt in class. Or, students can use the worksheets to revise. These worksheets can also be assigned as homework. There are four categories of worksheets: Reinforcement, Extension, Assessment and tests, and Investigate. Answer keys are provided in the Aula Virtual and on the website: http://www.evocacion.es Worksheets Reinforcement worksheets There are two pages of Reinforcement worksheets for each topic. These worksheets are designed to provide additional support for students in need of further practice. They can be used after the relevant section in the Student’s Book, before the Final activities sections, or as extra preparation for the Unit assessment. Students can complete the worksheets with or without consulting their Student’s Books, in the classroom or at home, individually or in pairs. Extension worksheets There are two pages of Extension worksheets for each topic. These worksheets can be used for fast finishers or to expand on the material covered in class. IV Assessment worksheets There are two pages of Assessment worksheets for each topic. They can be given out once the topic has been completed, as a revision test, or to check progress during the year. Tests and Investigate There is a multiple-choice test for each topic. The tests provide students with the opportunity to revise the main concepts of each topic and to assess the knowledge they have acquired. There is an Investigate worksheet for each topic. These worksheets provide opportunities for students to carry out simple investigative tasks, either in the classroom or at home. V Life processes REINFORCEMENT Name 1 Date Colour the correct word. Then, write the sentence. electricity • Nutrition provides your body with energy and nutrients. 2 3 Match each process involved in nutrition to its body system. a. digestion circulatory sytem b. respiration digestive sytem c. circulation excretory sytem d. excretion respiratory sytem Put the words in order to complete the diagram. locomotor system – sense organs – nervous system • Sensitivity is a constant process. It involves different systems and organs in the body: 6 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 4 Circle the parts of the locomotor system. Then, classify them. femurp al ector vicle scla humerusabdominalspelvis skeletal system 5 bice psqu adriceps muscular system Read and write T (true) or F (false). Then, correct the false sentences. a. The process of reproduction allows us to have offspring similar to ourselves. b. People have sexual reproduction. c. People are oviparous. d. Male reproductive organs and female reproductive organs are different. e. Reproductive organs develop during adulthood. 6 Unscramble the letters and complete the sentences with the correct words. cegnyparn a. resutu dofo arce klim lasts about nine months. b. During this period, the baby develops and grows inside the c. The baby receives and oxygen from the mother. d. Newborn babies need constant attention and e. Newborn babies drink their mother’s Photocopiable material © 2015 Santillana Educación, S.L. . from their parents. . Natural Science 4 7 Life processes Name EXTENSION Date Broken bones Bones are hard, strong and rigid, but they can sometimes break or fracture. However, broken bones can repair themselves. There are many different types of fractures. The most common type is a simple fracture, which happens when a bone breaks cleanly. In order to help bones heal correctly, it is important that they are realigned. Broken bones can be put back into position by a doctor. The bones are then immobilized with a plaster cast, so they can start to heal. Simple fractures usually take about 6 to 8 weeks to heal, although large bones take longer. 1 Write T (true) or F (false). a. Bones break because they are rigid. b. Bones can repair themselves. c. The most common fracture is when a bone breaks into fragments. d. Broken bones need to be realigned, then immobilized. e. All fractures take about 6 to 8 weeks to heal. f. A fracture of the femur takes the same time to heal as a fracture of the radius. 2 Have you ever broken a bone or do you know someone who has? Complete the medical card. medical card Who broke a bone? Which bone was it? How did they break it? How many weeks did it take to heal? 8 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Life processes EXTENSION Name Date Breast milk After a baby is born, the mother’s breasts start producing milk. Breast milk is the most nutritious food for babies. The quantity of milk produced by the mother depends on how much the baby nurses. The more the baby nurses, the more milk the mother produces. The composition of breast milk changes. The first milk is called colostrum. It is thick and yellowish. It has many nutrients and substances to protect the newborn baby against infections. A few days later, breast milk becomes more creamy and white. It has all the nutrients the baby needs to grow. The composition of breast milk can change depending on what the mother eats. 1 Read the text and answer the questions. a. Which is the most nutritious food for babies? b. What is the first milk called? c. What does this milk protect the baby against? d. What does breast milk contain? e. What can change the composition of breast milk? 2 Ask your parents. Then, complete the table. you your friend Were you breastfed? How long for? Were you bottle-fed? How long for? Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 9 Life processes ASSESSMENT Name 1 Date Complete the sentences with the processes involved in nutrition. a.During , oxygen and nutrients are carried in the blood. b. During , you absorb the nutrients your body needs from food. c. During , you breathe in air and obtain the oxygen you need. d.During , you expel the waste materials that your body does not use. 2 Write the name of each system. 3 Match the organs of the nervous system to their functions. interprets information received from the sense organs nerves brain carry information from the sense organs to the brain makes decisions and sends orders to the locomotor system carry orders from the brain to the locomotor system 10 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 4 Write the names of the systems. Then, label the systems. cranium clavicle vertebrae a b ulna pelvis deltoid pectorals d e a. b. c. radius d. c f fibula e. f. tibia 5 Use the groups of words to write three sentences about reproduction. reproduction offspring similar people sexual reproduction viviparous male female reproductive organs 6 Match the two halves to make complete sentences about reproduction. a. The baby develops and oxygen from the mother. b. Pregnancy lasts about nine months. c. The baby receives food their mother’s milk or artificial milk. d. Babies drink inside the mother’s uterus. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 11 Life processes TEST Name 1 Date Nutrition provides your body with... a. air and nutrients. b. nutrients and energy. c. air and energy. 2 You absorb the nutrients your body needs during… a. respiration. 3 c. circulation. b. brain c. stomach. The excretory system eliminates… a. nutrients. 6 b. respiration. The main organ of the circulatory system is the… a. heart. 5 c. digestion. You obtain the oxygen your body needs through… a. digestion. 4 b. excretion. b. waste. c. air. The process of sensitivity involves the sense organs,… a. the skeletal system and the muscular system. b. the nervous system and the locomotor system. c. the nervous system and the muscular system. 7 The locomotor system includes… a. bones and muscles. b. bones, joints and muscles. c. bones, joints, muscles and tendons. 8 Reproduction allows us… a. to have offspring similar to ourselves. b. to respond to changes in the environment. c. to obtain nutrients. 9 Reproductive organs develop during… a. childhood. b. adolescence. c. adulthood. 10 During pregnancy, the baby develops… a. in the mother’s uterus for three months. b. in the mother’s ovaries for nine months. c. in the mother’s uterus for nine months. 12 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Life processes INVESTIGATE Name 1 Date Which foods contain fat? Instructions 1. In pairs, select five or six different foods, for example, an apple, chips, a banana, biscuits, a carrot, bread or cheese. Cut them into pieces. 2. Cut some brown wrapping paper into five 10 cm squares. 3. Rub a piece of each food on a square of paper until it leaves a mark. Label the squares and allow the marks to dry. 4. When dry, hold the squares against the light. If there is a grease spot, the food contains fat. Measure the diameter of each grease spot with a ruler. The size of the grease spot tells us how much fat there is in the food. 5. Complete the table. food diameter of grease spot fat no fat 6. Analyse your results and answer the questions. a. Which food leaves the biggest grease spot? b. Which is the food with the least fat? c. Which is the food with the most fat? Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 13 Your senses REINFORCEMENT Name 1 Date Unscramble the words and label the diagram. siir 2 taneri anceor uplip cpoti erevn nesl Circle the five parts of the ear and complete the sentences. audito r ryne arca e e v nalcochleasmall bo nes eardr a. Sound vibrations go into the outer ear and along the b. The . vibrates. c. The vibration of the eardrum moves the three d. The sound then goes to the e. The cochlea sends the sound through the 14 Natural Science 4 um . . to the brain. Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 3 Read and complete the table. smell taste touch The sense organ is… It allows you to capture or identify… 4 5 Match the parts of the organs to their function. a. taste buds captures light b. epithelium capture flavours of food c. touch receptors captures sound d. retina distinguish hot or cold e. cochlea captures smells Label the diagram of the nose. nostril olfactory nerve Photocopiable material © 2015 Santillana Educación, S.L. olfactory bulb nasal cavity olfactory epithelium Natural Science 4 15 Your senses EXTENSION Name Date Guide dogs Guide dogs act as eyes for people who are blind. They help blind people move from one place to another. They can help a blind person cross the road, avoid obstacles or go to the shops. Guide dogs stay with their owners at all times. Most guide dogs are Labradors or Golden Retrievers. They receive special training starting when they are puppies. Then, they are assigned to a blind person. Guide dogs wear a harness to do their job. Guide dogs work for approximately six years before they retire. 1 Write T (true) or F (false). a. Guide dogs help people who cannot see. b. They sometimes leave their owners alone. c. Their harness is just for decoration. d. All breeds of dogs can be guide dogs. e. They have a limited working life. 2 Complete the index card about guide dogs. Guide dogs Job description: Most common breeds: Equipment: Years of service: 16 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Your senses Name EXTENSION Date Sign language People with sight and hearing disabilities use different languages to communicate with other people. Sign language is a language that many deaf people use to communicate. Braille is a system of printing for blind people. 1 Use the sign alphabet. Learn to say your name with your hands. Take turns with a partner to spell out your name. 2 Use the Braille alphabet. Punch out your name on a piece of card with the tip of a ballpoint pen. Learn to read it with your fingers. Exchange names with a partner. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 17 Your senses ASSESSMENT Name 1 Date Write the five sense organs. 2 Label the parts of the eye. 3 Read and complete. eyelids – optic nerve – pupil – brain – sight a. The eyes are the sense organs of . b. The , eyelashes and eyebrows protect the eyes. c. The is the hole in the centre of the iris though which light passes. d. When we see an object, the information is sent to the the 4 18 through . Label the parts of the ear. Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 5 Circle the correct word. a. The pinna / cochlea captures the sound. b. The cochlea sends the sound through the ear canal / auditory nerve to the brain. c. The brain interprets / vibrates the information. 6 What part of your nose captures smells? 7 Complete the sentences. a. Touch is the of the objects around you. which allows you to identify characteristics b. The sense organ of touch is the 8 Label the diagram of the skin. 9 Write the corresponding sense organ. d. iris ▶ b. nasal cavity ▶ e. pupil ▶ c. taste buds ▶ f. auditory nerve ▶ a. cochlea ▶ . 10 Give advice to look after your eyes and ears. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 19 Your senses TEST Name 1 We can only see if there is… a. light. 2 Date b. sound. c. colour. The eyes are… a. connected to the brain by the auditory nerve. b. protected by the eyelids, the eyelashes and the eyebrows. c. made up of three parts. 3 The part of the ear that vibrates is the… a. eardrum. 4 c. brain. b. the skin. c. hair. The smell receptors are in the… a. olfactory epithelium. 7 b. inner ear. The sense organ of touch is… a. the finger. 6 c. pinna. The auditory nerve takes the information to the… a. outer ear. 5 b. cochlea. b. olfactory bulb. c. nostrils. Umami is… a. the most important taste bud. b. the fourth basic flavour. c. a flavour found in strong cheeses. 8 You should not touch your eyes… a. in strong sunlight. b. in the swimming pool. c. with dirty hands. 9 When using headphones, you should… a. keep the volume low. b. keep the volume high. c. turn off the sound. 10 Doctors for children are called… a. podiatrists. 20 Natural Science 4 b. paediatricians. c. physicians. Photocopiable material © 2015 Santillana Educación, S.L. Your senses INVESTIGATE Name 1 Date What happens when you can’t see what you are tasting? And when you can’t see or smell what you are tasting? orange juice mustard mayonnaise ketchup yoghurt pineapple juice Instructions 1. Work with a partner. 2. Your partner wears a blindfold. 3. Dip a plastic spoon in one of the foods and let your partner taste it. 4. Ask your partner to identify the food. 5. Repeat the experiment in a different order. This time your partner holds their nose. 6.Can you identify the food? Complete the table with the results. Take turns and compare the results. food blindfolded blindfolded and holding your nose pineapple juice yes no Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 21 The circulatory system REINFORCEMENT Name 1 Date Use the colour key to circle the words. give us energy ▶ red help us grow ▶ blue keep us healthy ▶ green fish – meat – grapes – eggs – rice – olive oil – pasta – bacon – pulses – carrots – bread – butter – strawberries – lettuce – cheese 2 Colour the parts of the circulatory system in red. heart mouth 3 22 lungs blood arteries stomach ears veins capillaries Label the circulatory system with the correct words from Activity 2. Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 4 Read and write T (true) or F (false). Then, correct the false sentences. a. The respiratory system moves blood around our body. b. Blood transports nutrients, oxygen and waste substances. c. Blood is mainly made up of red blood cells. d. Arteries, veins and capillaries are blood vessels. e. The thorax pumps blood around the body. 5 Unscramble the words and complete the text. nucalircito Blood dobol ygnoxe tentusrin satwe is the constant movement of blood in the blood vessels. transports of the body. It helps to eliminate 6 and to all parts substances. Draw two healthy habits which are good for the circulatory system. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 23 The circulatory system EXTENSION Name Date Long live the hamburger! I bet you think hamburgers are a modern food. Believe it or not, the origin of the hamburger goes all the way back to ancient Egypt! The name ‘hamburger’ comes from the German city of Hamburg, where it was very popular in the 14th century. At this time, the hamburger began to look like the ones we see today: a flat cake of minced beef, placed between two slices of bread. The hamburger arrived in Britain in the 19th century. After that, the British introduced this food to the USA. Nowadays, the hamburger is one of the most popular meals in the world. 1 Read and answer the questions. a. Who made the first hamburgers? b. Where does the name ‘hamburger’ come from? c. What were hamburgers like in the 14th century? d. What country introduced hamburgers to the United States? 2 Draw and write about your favourite hamburger. My favourite hamburger Name: Ingredients: Main nutrients: 24 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. The circulatory system EXTENSION Name Date Our amazing heart The human heart is a small, but very powerful organ. A child’s heart is about the size of a fist. In an adult, it is about the size of two fists. The heart weighs between 250 and 350 grams. The heart’s strong muscles are constantly working, making it beat on average 72 times a minute. That’s 100,000 times a day and about 35 million times a year! All these heartbeats make the heart pump about 5 litres of blood per minute around the body. That’s about 7,200 litres of blood per day, which means over 2 million litres per year! 1 Read the text and complete the table about the heart of an adult. weight 2 number of heartbeats a minute a day a year Circle the correct words. a. The human heart is a big / small, but very powerful organ. b. A child’s heart is about the size of a foot / fist. c. The heart weighs between 250 and 350 grams / kilograms. d. The heart’s muscles make the heart beat on average 72 / 84 times a minute. 3 What is a stethoscope? Search the Internet for information about stethoscopes and write a short definition of this instrument. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 25 The circulatory system ASSESSMENT Name 1 2 Date Read the sentences and match. a. These help our digestive system work correctly. water b. We need this to grow. meat c. These give us energy. oranges d. We need these to stay healthy. green beans e. We need to drink at least two litres a day. sausages Circle the main organs in the body. Then, classify them. heartsto h mac digestive system 3 eyslu n d i k ngsintestinesblood respiratory system ves circulatory system sels trachea excretory system Read the sentences and write the words. closed circuit – veins – capillaries – heart – blood – arteries – waste a. It transports nutrients, oxygen and waste substances. b. They carry blood from the heart to all other parts of the body. c. They carry blood back to the heart. d. They connect arteries to veins. e. It pumps blood around the body. f. Blood takes this to the excretory system. g. The heart and blood vessels make up this. 26 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 4 Label the diagram. Then, complete the text. ribs – sternum – spinal column – heart The thoracic cavity includes the . It protects the 5 , the and the . Read the sentences and underline the mistakes. Then, write the correct sentences. a. Nutrition involves the digestive, respiratory, circulatory and excretory organs. b. Blood is a very important liquid mainly made up of nutrients. c. The types of blood vessels are: veins, kidneys and arteries. 6 Match and write two healthy habits for the circulatory system. a. We need to do a healthy and balanced diet. b. We should eat exercise regularly. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 27 The circulatory system Name 1 Date Nutrition provides your body with... a. air and nutrients. 2 TEST b. nutrients and energy. c. air and energy. The four processes of nutrition are… a. digestion, respiration, sensitivity and excretion. b. digestion, reproduction, circulation and excretion. c. digestion, respiration, circulation and excretion. 3 Carbohydrates, fats, proteins, vitamins and minerals are… a. nutrients. 4 c. food. Each process of nutrition takes place in… a. an organ. 5 b. energy. b. a system. c. the whole body. The circulatory system is made up of… a. blood, blood vessels and the heart. b. blood, arteries and veins. c. blood, capillaries and the heart. 6 Blood is mainly made up of… a. nutrients. 7 b. red blood cells. c. water. Blood vessels include… a. arteries, veins and tubes. b. arteries, veins and capillaries. c. arteries, tubes and capillaries. 8 The heart is a powerful organ made up of… a. blood. 9 b. bones. c. muscles. Blood circulation is the constant movement of blood through the… a. heart. b. arteries. c. blood vessels. 10 In order to keep our circulatory system healthy, we need… a. to eat a diet high in carbohydrates and do regular exercise. b. to eat a healthy diet and do occasional exercise. c. to eat a healthy diet and do regular exercise. 28 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. The circulatory system INVESTIGATE Name 1 Date How much exercise do you do every week? Instructions 1. Record the types of exercise you do each day for a week. Include physical activity and/or sport. 2. Then, write down how long you spend doing each type of exercise. 3. At the end of the week, add up the number of hours you exercise per day to calculate the total number of hours you exercise per week. type of exercise hours and minutes Monday Tuesday Wednesday Thursday Friday Saturday Sunday total time 4. In small groups, share your records and discuss the types of exercise you do, the time spend exercising, and the total time you exercise in a week. 5. Write a conclusion: I do Photocopiable material © 2015 Santillana Educación, S.L. of exercise in a week. Natural Science 4 29 Respiration and excretion REINFORCEMENT Name 1 Date Unscramble the letters and label the diagrams. snugl 2 c a h a t e r s o n e n h i r b c o Complete the sentences about respiration. lungs – exhalation – inhalation – leaves – expands – contracts – enters – oxygen a. Air reaches our lungs through respiration. When we breathe in, the thorax and air is called the lungs. This breathing movement . b. When we breathe out, the thorax and air the body. This breathing movement is called c. Inhaled air reaches the . , and the in this air passes into the blood. 3 Read the clues and complete the parts of the excretory system. Then, put them in order. a. It stores the urine until it is expelled from the body. b. It is the tube through which urine is expelled. c. They filter the blood and make urine. 30 Natural Science 4 d r d Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 4 Label the diagram of the excretory system. 5 Read and complete the text about sweat. mineral – skin – cool – clean – blood – waste Sweat keeps our body our blood when it gets too hot, but it also helps to keep . It is made up of water, salts and waste substances from the , these 6 7 . When we sweat through our substances are expelled. Read the phrases about harmful substances and match. a. Substances found in glue and cleaning products. pollutants b. A very harmful substance with toxic ingredients. toxic substances c. Substances produced by cars and factories. cigarette smoke Tick (✓) the photos of healthy habits. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 31 Respiration and excretion EXTENSION Name Date What is asthma? Asthma is a very common illness among children. The bronchi become inflamed, so air cannot travel freely to the lungs. Children who have asthma experience wheezing (a whistling sound in the chest), coughing and difficulty breathing. Asthmatic children usually carry an inhaler. This is a small tube with medicine in it. The medicine helps to open the bronchi. People with asthma also have to be careful about their environment. Many different things can cause an asthma attack: cold air, exercise, tobacco smoke, cat hairs and even swimming pools! But children with asthma can do everything other children can do. They just need to take precautions. In fact, many Olympic champions and other athletes have asthma, for example, David Beckham and Miguel Indurain. 1 Read and write T (true) or F (false). Then, correct the false sentences. a. Asthma is a disease of the circulatory system. b. An inhaler helps asthmatic children to breathe. c. The environment affects asthma a lot. d. Children with asthma cannot play like other children. 2 Use the code and find a tip for asthma prevention. •5A ♥5K ∧ 5B ♦5M • ≅ ♠ ⊃♣ 32 ♣5D ∅5S ∪5E ∗ 5T ∗ ♠ ∧ • ≈ ≈ ♠ 3 ≈5C ♠5O ⊃5I ≅ 5V ∅♦♠♥∪ ! Interview your classmates. Find out who has asthma and how they treat it. Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Respiration and excretion Name EXTENSION Date Our natural cleaning machines The kidneys are part of the body’s waste disposal system. These little, but efficient cleaning machines are about the size of a computer mouse and weigh between 120 and 170 grams. Our kidneys filter about 200 litres of blood and make an average amount of 1.5 litres of urine every day. They filter all the blood in the body every thirty minutes, about forty times a day! In addition, kidneys adjust the volume of liquids in your body, so if you are sweating a lot, or you are not drinking enough liquids, they produce less urine. The kidneys also help to make red blood cells when needed. In order to look after our kidneys, we should drink between 6 to 8 glasses of water a day. 1 Read the text and answer the questions. a. How much do our kidneys weigh according to the text? b. Why are kidneys considered cleaning machines? c. What other important jobs do they perform? d. How much water should we drink daily? 2 Do you drink enough water? Complete the table. Monday Tuesday Wednesday Thursday Friday Saturday Sunday number of glasses Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 33 Respiration and excretion Name 1 ASSESSMENT Date Read the sentences and write the organ or part of the respiratory system. a. Two small tubes each connected to a lung. b. The part of the respiratory system where air enters the body. c. Two spongy, elastic organs that are protected by the thoracic cavity. d. A tube that connects the nose and the lungs. 2 Look at the diagram and circle the correct words. a. When we inhale / exhale, the thorax expands / contracts and air enters the lungs. This is called inhalation / exhalation. b. When we inhale / exhale, the thorax expands / contracts and air is expelled from the body. This is called inhalation / exhalation. 3 Unscramble the letters and label the diagram. Then, write the name of the system. indysek rhature berldad • This is the 34 Natural Science 4 system. Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 4 Complete the sentences with the correct words. urethra – expelled – urine – filter – kidneys a. The are the main organs in the excretory system. They the blood and make urine. b. The bladder is the organ where until it is from the body. c. The 5 is stored is a tube through which urine is expelled. Tick (✓) the photo of a healthy habit for the respiratory system. Then, write three examples of harmful substances. a. b. c. 6 Use the words to write two healthy habits. skin drink keep water a. b. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 35 Respiration and excretion Name 1 Date To obtain energy from nutrients, we need... a. oxygen. 2 TEST b. nitrogen. c. air. The respiratory system is made up of… a. the nasal cavity, the trachea, the bronchi and the lungs. b. the nose, the trachea, the bronchi and the lungs. c. the nose, the trachea, the bronchi and the kidneys. 3 In the lungs, oxygen from the air passes into the… a. bronchi. 4 c. respiration. b. nutrients. c. waste substances. The cleaning of blood takes place in the… a. respiratory system. 7 b. exhalation. Blood travels through our body and collects… a. oxygen. 6 c. ribs. The thorax contracts during… a. inhalation. 5 b. blood. b. circulatory system. c. excretory system. The production, storage and elimination of urine take place respectively in the… a. kidneys, bladder and urethra. b. bladder, kidneys and urethra. c. kidneys, urethra and bladder. 8 Sweat is mostly made up of… a. mineral salts. 9 b. water. c. waste substances. Harmful substances for our respiratory system include… a. pollutants, toxic substances and cigarette smoke. b. pollutants from factories, paint and glue. c. pollutants from cars, cleaning products and cigarette smoke. 10 Drinking enough water helps to look after our… a. circulatory system. b. excretory system. c. respiratory system. 36 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Respiration and excretion Name 1 INVESTIGATE Date How do your sweat glands work? Instructions 1. We have around two million sweat glands in our skin, throughout the body. We are going to observe the sweat glands in the palms of our hands. 2. Work in pairs. You need a glass of water, 100 ml of starch, some iodine solution, a beaker, a spoon, small paper squares (6 cm x 6 cm) and some glue. 3. Mix the water and starch. Stir the solution with the spoon. Wet the paper squares with the solution. 4. Cover your partner’s palm with iodine solution (it is toxic, so do not drink or taste it). 5. Ask them to rub their hands together for a few minutes, until their palms are sweaty. 6. Press a paper square against your partner’s palm and observe what you see on the paper. 7. Switch roles and repeat the experiment. 8. Then, write a description of your observations and glue the paper square on the index card. Sweat glands in your palm Observations: Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 37 Reproduction REINFORCEMENT Name 1 Date Read the sentences about changes during puberty and write girls or boys. a. They have a lower voice. b. They have wider hips. c. They develop breasts. d. They develop an Adam’s apple. 2 Circle the organs of the reproductive system. Then, classify them. ovarieste vag stes inavulvaprostateglan female reproductive organs 3 38 dute ruspenis male reproductive organs Read the sentences about the baby. Then, match them to the correct picture. a. The head, limbs and heart are fully formed. c. It is as small as a pea. b. It moves a lot inside the mother’s uterus. d. It is about fifty centimetres long. Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 4 Write T (true) or F (false). Then, correct the false sentences. a. The muscles of the mother’s uterus contract and push the baby out. b. The navel is the scar formed on the baby after cutting the umbilical cord. c. Pregnancy is the process by which a baby is born. d. The baby leaves the mother’s uterus through the vulva. 5 Copy the words in the correct order to make sentences about healthy habits for pregnant women. should have a. lots of fruit and vegetables They and eat a varied diet light exercise b. and swim should do and walk They enough sleep c. They with their legs up and rest should get 6 Complete the sentences about babies. skin – hair – head – navel – hands a. Their is thin and rosy. b. Their needs time and care to heal. c. Their are often closed in a fist shape. d. Their is soft and thin. e. Their is very delicate. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 39 Reproduction Name EXTENSION Date The magic of ultrasound Have you ever seen an ultrasound image? Ultrasound scans are performed on women during pregnancy. They work by using sound to produce images of the baby. Ultrasound images show many details, for example, the baby’s heart, its brain, its arms and legs, and its eyes and mouth. If the baby is in the right position, they can even show if it is a boy or a girl. These images can also detect movement, including the baby’s heartbeat! Ultrasound scans are performed at different stages of pregnancy. In this way doctors can monitor the growth and development of the baby in the uterus. They can measure the body parts, such as the skull or the legs’ bones to see if growth is normal. These days, you can have your photo taken before you are born! 1 Read the text and answer the questions. a. How do ultrasound images work? b. What can you see in them? c. What else can ultrasound images detect? d. When are ultrasound scans performed? e. What can doctors measure with ultrasound scans? 2 Look at an ultrasound image of a baby. Try to identify the different body parts. In this ultrasound image, I can see… 40 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Reproduction EXTENSION Name Date Why do people have different skin colour? Human skin colour varies greatly around the world. It can range from very dark brown to yellow. Skin colour is controlled by genes, like other human characteristics such as eye colour and hair type. However, skin colour has also been influenced by the environment over thousands of years. There are many different skin colours today because people have adapted to different environments. The Sun gives us light and heat, but it also emits harmful rays. Some regions of the Earth receive more harmful sun rays than others. This difference directly affects skin colour. Skin colour depends on how much melanin we have in our skin. Melanin is a brown pigment that works as a natural sun cream, and protects skin from the harmful rays of sunlight. Over time, people who moved to areas of less sunlight developed lighter coloured skin, and people who lived closer to the Equator had darker skin with more melanin. 1 Read the text and complete the sentences. a. Skin colour is controlled by b. The Sun . harmful rays. c. Skin colour depends on the d. Melanin of melanin. the skin from the harmful rays of sunlight. e. People with lighter skin have 2 melanin. Search the Internet or magazines for photos of three famous people with different skin colour. Write their names and the continent they come from. dark skin Photocopiable material © 2015 Santillana Educación, S.L. medium skin light skin Natural Science 4 41 Reproduction Name 1 ASSESSMENT Date Match and write the sentences. a. Reproduction allows to mature during puberty. b. People have sexual reproduction and are viviparous. c. Sexual organs begin people to have offspring. d. Physical changes during puberty are different for men and women. 2 Look and label the diagrams. Then, write the name of each system. uterus — testes — penis — vagina — ovaries — prostate gland — vulva 3 Read and circle the correct words. a. The baby is ready to be born at six / nine months. b. The baby is as small as a pea after a few weeks / three months. c. The baby is about thirty centimetres long at three / six months. d. The baby has the head, heart and limbs fully formed at three / nine months. 42 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 4 Write a sentence with each group of words. birth baby process born a. baby mother’s uterus leaves vagina b. push muscles mother’s uterus contract c. scar umbilical cord navel d. 5 Circle the words related to a healthy pregnancy. Then, write two healthy habits. check-ups fatty foods fruit and vegetables water ultrasound lots of salt swim cigarette smoke walk paediatrician alcohol a varied diet 6 Write a recommendation on how to care for a newborn baby’s... a. head ▶ b. hair ▶ c. navel ▶ d. feeding ▶ Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 43 Reproduction TEST Name 1 The process of reproduction allows people to have… a. sons. 2 c. offspring. b. body. c. belly. Sexual organs mature during… a. adulthood. 4 b. daughters. Babies develop in their mother’s… a. uterus. 3 Date b. adolescence. c. childhood. The internal organs of the female reproductive system are… a. the vulva, the vagina and the ovaries. b. the vulva, the uterus and the ovaries. c. the uterus, the vagina and the ovaries. 5 The external organs of the male reproductive system are… a. the penis and the testes. b. the penis and the prostate gland. c. the testes and the prostate gland. 6 The baby receives nutrients and oxygen through the… a. uterus. 7 c. ovaries. b. a year. c. 6 months. Pregnancy lasts about… a. 9 months. 8 b. umbilical cord. At birth, the muscles of the mother’s uterus… a. contract and push the baby out. b. relax and push the baby out. c. contract and relax. 9 Pregnant women should have a varied diet,… a. do light exercise and get enough sleep. b. do intense exercise and get enough sleep. c. do light exercise and get little sleep. 10 Newborn babies drink… a. their mother’s milk or fruit juice. b. water or artificial milk. c. their mother’s milk or artificial milk. 44 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Reproduction INVESTIGATE Name 1 Date How much does a mother’s weight increase during pregnancy? During pregnancy, the weight of the future mother increases as the baby grows inside the uterus. Instructions 1. Work in pairs. 2. The following graph shows Natalie’s weight during her pregnancy. Weight in kg Natalie’s weight during her pregnancy 68 67 66 65 64 63 62 61 60 59 58 57 56 55 Initial weight Month 1 Month 2 Month 3 Month 4 Month 5 Month 6 Month 7 Month 8 Month 9 3. Study the graph with your partner and answer the questions. a. What was Natalie’s weight at the beginning of her pregnancy? b. What was her weight at the end of her pregnancy? c. How much weight did she gain throughout the pregnancy? Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 45 People and health REINFORCEMENT Name 1 2 Date Read and match. a. Our emotions are not a problem in our daily activities. physical health b. We have good relationships with our family and friends. mental health c. Our body processes, such as respiration and digestion, occur normally. social health Colour in blue the words about prevention of illness. medicines vaccinations symptoms 3 illness medical specialists treatment check-ups fats sugar Circle the healthy habits. A D 46 healthy habits Natural Science 4 B C E F Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 4 Tick (✓) the most common foods in a healthy diet. 5 Unscramble the letters and complete the sentences about healthy eating habits. samel gehiyne a. Pay attention to food vorespinerat . b. Eat five a day. c. Pay attention to food 6 . Read the key about accident prevention and write the correct letter. A = home accident prevention B = school accident prevention C = street accident prevention a. Use a booster seat and a seat belt when in a car. b. Use electrical devices and plugs safely. c. Don’t run in the classrooms or along the corridors. d. Handle sharp objects carefully. e. Walk carefully on stairs and never push classmates. f. Don’t run on the pavement. g. Wear a helmet when riding your bike. h. Don’t take other people's medicines. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 47 People and health EXTENSION Name Date Sleeping and dreaming Sleep is very important for keeping healthy. When we sleep enough we pay better attention at school. We will be in a better mood and solve problems more efficiently. Children need to sleep ten hours a night. Everybody dreams every night. In one night, we can have four to seven dreams. The things we dream about can be related to our friends and family, our favourite TV shows, or something we are happy about or worried about. We do not always remember our dreams. We forget most of them when we wake up. Animals dream too. Have you ever watched a dog while it is sleeping? Many dogs move their paws when they sleep as if they were running. 1 Put the words in order to make sentences. hours to sleep need a night ten Children a. dreams In one night, four to seven have can we b. always We our do dreams not remember c. 2 Koalas sleep 22 hours a day! Search the Internet and find out how many hours your favourite animal sleeps. 48 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. People and health Name EXTENSION Date Living for over a hundred years The Japanese island of Okinawa has one of the largest populations of people over a hundred years old. The Italian island of Sardinia in the Mediterranean Sea also has a high number of centenarians. Doctors are trying to explain why Okinawa and Sardinia are so special. What helps people live to be over a hundred? There are several reasons for this. In Okinawa the climate is mild, people have a healthy diet and they do a lot of exercise in the fresh air. And they are always in a good mood! Apparently, the reasons in Sardinia are similar: mild weather, healthy lifestyle and strong social relationships. 1 Read the text and answer the questions. a. Who are centenarians? b. Which two places in the world have a large centenarian population? Where are they? c. Why do people live such long lives in Okinawa? d. What about in Sardinia? 2 Search the Internet to find out about the five oldest people in the world. Write their names, age and country of origin. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 49 People and health Name 1 ASSESSMENT Date Read and classify the words. people – body – processes – emotions – relationships – pain – ourselves 2 physical health mental health social health Tick (✓) the correct boxes. prevention health care Getting vaccinations Taking medicine prescribed by the doctor Going to the doctor when you are ill Having healthy habits Going to the doctor for a check-up Visiting medical specialists 3 50 Read and match. a. Keeping your back straight when you are sitting. hygiene b. Brushing your teeth after every meal. sleep c. Practising sports. posture d. Visiting an amusement park. physical exercise e. Sleeping ten hours a day. leisure activities Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 4 Write T (true) or F (false). Then, correct the false sentences. a. Visiting a museum is a leisure activity. b. Good posture helps you to prevent hand pain. c. You should wash your hands once a day. d. Physical exercise makes you stronger and more flexible. e. Children need to sleep eight hours a day. 5 Match the two halves and write complete sentences. a. Eat a variety of foods to get fruit, vegetables and pulses. b. Reduce fats of animal origin, cakes, sweets and fizzy drinks. c. Eat plenty of fibre found in all the nutrients your body needs. d. Reduce sugar found in such as bacon and butter. 6 Look at the pictures and write an accident prevention recommendation for each. A B C Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 51 People and health TEST Name 1 Date Health is a state of complete physical, mental and… a. emotional well-being. b. corporal well-being. c. social well-being. 2 We can feel many different emotions such as … a. anger, happiness, sadness and love. b. anger, hunger, shyness and surprise. c. fear, love, thirst and happiness. 3 Conflicts should be… a. avoided. 4 b. curing illness. c. preventing illness. A children’s doctor is called… a. a psychologist. 6 c. ignored. Vaccinations are used for … a. treating illness. 5 b. resolved properly. b. a paediatrician. c. a physician. You should brush your teeth… a. before going to bed. b. when you get up in the morning. c. after every meal. 7 Children need to sleep… a. ten hours a day. 8 b. seven hours a day. c. six hours a day. Physical exercise makes you … a. stronger and more flexible. b. thinner and taller. c. happier and more relaxed. 9 A healthy diet includes… a. lots of fats of animal origin. b. foods with lots of sugar. c. a variety of foods and plenty of fibre. 10 Accidents cannot be avoided, but they can often be… a. predicted. 52 Natural Science 4 b. prevented. c. expected. Photocopiable material © 2015 Santillana Educación, S.L. People and health Name 1 INVESTIGATE Date How many hours do you sleep a day? Getting enough sleep is essential to stay healthy. Instructions 1. You are going to record how many hours you sleep per day for a week. 2. Write the time you go to bed and the time you wake up every day. Calculate the hours you sleep and record your results in the table. Monday Tuesday Wednesday Thursday Friday Saturday Sunday hours of sleep 3. At the end of the week, look at the table and answer the questions. a. Did you sleep the same number of hours every day? b. Do you sleep the same number of hours on weekdays as at weekends? c. Which day did you sleep the most hours? d. Which day did you sleep the least hours? e. How many hours do you sleep on average? f. Do you think you are a good or a bad sleeper? Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 53 Classifying living things REINFORCEMENT Name 1 Date Find the five main groups of living things and label the photos. A B b a c t e r i a n l s t y a i n s g t f u n g i t a d p a b g m g e s u l s a a h l z x q e r l o n p l a n t s E D C 2 Read the groups of animals and classify. cnidarians – amphibians – echinoderms – mammals – sponges – molluscs – birds – worms – reptiles – arthropods – fish vertebrate animals 54 Natural Science 4 invertebrate animals Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 3 Read the sentences and write animals or plants. a. Most of them can be seen with the naked eye. b. Most of them can move about. c. They make their own food. d. They cannot move about. e. They feed on other living things. 4 Unscramble the letters and write the words under the correct type of fungi. estysa A 5 smormhuso B duslom C Write T (true) or F (false). Then, correct the false sentences. a. Fungi can make their own food. b. Yeasts are used to make bread and cheese. c. Bacteria are the smallest and simplest living things. d. Bacteria feed on other living things. e. Some bacteria are helpful and some cause illnesses. f. Algae have roots, leaves and stems. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 55 Classifying living things Name EXTENSION Date Algae: delicious and good for you! Marine algae, often called seaweed, are an important part of many people’s diet, particularly in east Asia. Nowadays, more Europeans are eating algae too. Algae, which some people refer to as sea vegetables, are very nutritious. They are rich in calcium, iron and minerals. In addition, algae can add flavour and texture to many raw dishes. Sushi, a traditional Japanese dish, is probably the most popular example. Sheets of nori, a red seaweed, are used to wrap sushi rolls. You can cut up sheets of nori and sprinkle them on salads, too. Kelp buds are also good in salads, but first you have to soak them in water. Marine algae are important for other reasons too. They are an essential source of food and shelter for marine life. Also, through photosynthesis, algae are a major source of the Earth’s oxygen supply. 1 Read the text and complete the sentences. a. Marine algae can also be called 2 or . b. Algae are rich in . c. The most popular dish made with algae is . d. To make nutritious salads, you can add . e. Through photosynthesis, algae are a major source of . Search the Internet to find examples of algae and their uses. Write. 56 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Classifying living things Name EXTENSION Date The world of microbes Do you really know why you have to wash your hands before eating? Even when they look clean, your palms are covered with millions of microscopic living things called microorganisms or microbes. These very tiny living things, invisible to the naked eye, can only be seen through a microscope. Microbes are everywhere in our bodies. We have trillions of them that cover us inside and out. However, microorganisms are very important for our health. For example, microbes in the digestive system help us to digest food. Some microbes may cause illnesses, but most of them are beneficial. In fact, we could not live without them! 1 Read the text and answer the questions. a. What are microbes? b. Which instrument do we need to see them? c. How many do we have in our body? d. Are they important to our health? e. Are they mostly beneficial or harmful? f. Why is it important to wash your hands? 2 Look at the pictures and put them in order. 3 Search the Internet to find an example of a beneficial microbe. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 57 Classifying living things ASSESSMENT Name 1 Date Unscramble the letters and use the words to label the photos related to each group of living things. nugfi misnala A cerabita sltapn B legaa C D 2 E Tick (✓) the correct groups. animals plants algae fungi bacteria They make their own food. They feed on other living things. They can move about. They cannot move about. They can be seen with the naked eye. They can only be seen with a microscope. 58 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 3 Colour the vertebrates in green and the invertebrates in orange. reptiles molluscs cnidarians 4 worms fish birds sponges mammals arthropods amphibians Read the sentences and write mushrooms, yeasts or moulds. a. They grow on fruit, bread or cheese. b. They grow when the fungus is going to reproduce. c. They can only be seen through a microscope. d. They are the visible part of a fungus. e. They are used to make bread, wine or beer. 5 Match the two halves and write complete sentences about bacteria. a. They are the smallest and to observe them. b. Some bacteria live others can cause illnesses. c. Some are very useful and yoghurt, vinegar and medicines. d. We use bacteria to make simplest living things. e. You need a microscope inside other living things. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 59 Classifying living things Name 1 TEST Date Living things are classified into different groups if… a. there are more differences than similarities between them. b. there are more similarities than differences between them. c. there are no differences between them. 2 All living things are classified into five main groups: a. animals, plants, algae, mushrooms and bacteria. b. vertebrates, plants, algae, fungi and bacteria. c. animals, plants, algae, fungi and bacteria. 3 Animals are classified into… a. vertebrates and invertebrates. b. mammals and invertebrates. c. vertebrates and echinoderms. 4 Amphibians and reptiles are… a. invertebrates. 5 c. cnidarians. b. vertebrates. c. fish. Sponges and molluscs are… a. invertebrates. 6 b. vertebrates. Living things that make their own food include… a. plants, algae and some bacteria. b. animals, plants and algae. c. plants, fungi and algae. 7 Algae are… a. terrestrial. 8 b. aquatic. c. both. Animals and fungi… a. feed on other living things. b. cannot move about. c. live in water. 9 Mushrooms are the visible part of… a. yeasts. b. moulds. c. fungi. b. wine. c. medicines. 10 Bacteria are used to make… a. bread. 60 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Classifying living things INVESTIGATE Name 1 Date How does mould grow best? Instructions 1. Work in groups. You need three slices of bread, three plastic bags, a permanent marker, a dropper, a magnifying glass and water. 2. You are going to observe how mould grows on bread at different temperatures. 3. Using the permanent marker, label the plastic bags as follows: C 5 cold RT 5 room temperature W 5 warm 4. Using the dropper, add 20 drops of water to each slice of bread. 5. Put each slice in a bag and place the bags in the following locations: • bag C in the refrigerator • bag RT in the classroom • bag W on the window sill 6. Observe the different pieces of bread with a magnifying glass. Write your observations in the table. after 1 day after 3 days after 1 week bag C bag RT bag W 7. At the end of the week, write a conclusion. • Mould grows best on bread at Photocopiable material © 2015 Santillana Educación, S.L. temperature. Natural Science 4 61 Animals REINFORCEMENT Name 1 Date Use the colour key and circle the animals. mammal ▶ red bird ▶ yellow amphibian ▶ orange 2 reptile ▶ green fish ▶ blue Complete the table about vertebrates. mammals birds reptiles amphibians body covering scales reproduction breathing habitat 3 oviparous lungs terrestrial Complete the words using the clues. a. Parts of the body that allow fish to move. s b. Carnivore birds with sharp claws and beak. 62 fish p c. Aquatic mammals. c d. Process of changes in amphibians. m Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 4 Write the groups of invertebrates. Then, match them to the correct pictures. a. They are simple aquatic invertebrates. They live attached to rocks. They have sac-like bodies full of pores. They are . b. They have got poisonous tentacles and jelly-like bodies. Jellyfish are in this group. They are . c. They have got long, soft bodies and no legs. They live in soil, in water or inside other bodies. They are . d. Mussels, octopuses, squids and snails are in this group of invertebrates. They are . e. They are marine animals. Their skeleton is made of hard plates. Starfish and sea urchins are in this group. They are . f. They have got an articulated exoskeleton made up of external plates. Insects, arachnids, crustaceans and myriapods are in this group. They are 5 . Circle the correct word. • Invertebrates haven’t got a skeleton / spinal column. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 63 Animals EXTENSION Name Date Do animals sleep? Like humans, all animals need to sleep in order to restore their energy. When there is not much food available, animals save energy by sleeping. However, animals do not sleep when it is too cold or too hot, or when they feel threatened. The amount of sleep animals need varies. Koalas can sleep up to twenty hours a day, while giraffes only sleep for about two hours. In general, predators sleep longer than herbivores. Herbivores must be alert, so they cannot sleep for long periods of time. Some animals are diurnal, which means they are awake during the day. Others are nocturnal, which means they are awake all night. Each animal has a particular sleep routine. Many animals sleep lying down. Koalas curl around tree trunks, sloths hang from branches, rabbits hide in burrows, horses sleep standing up, bats sleep upside down, cows sleep with their eyes open, and seals sleep under water. 1 Read the text and answer the questions. a Why do animals sleep when there is not much food? b. Do animals sleep when they sense danger? c. Can you name three diurnal animals? d. Can you name three nocturnal animals? e. How do rabbits protect themselves while they sleep? 2 Search the Internet for information about animal sleeping habits and complete. animal 64 Natural Science 4 when they sleep how they sleep how many hours they sleep Photocopiable material © 2015 Santillana Educación, S.L. Animals EXTENSION Name Date How do dolphins communicate? Dolphins can emit many different sounds. These sounds produce echoes when they hit objects around them. Dolphins use the echoes to locate objects and living things around them. This process is known as echolocation. Dolphins estimate the distance from an object based on the time the echo takes to return to them. The farther away an object is, the longer it takes to hear the echo. Echolocation also allows dolphins to communicate. In an experiment performed with two dolphins in two separate water tanks, the dolphins took turns communicating with taps and whistles through an intercom. In fact, they had a real conversation! 1 Read the text and answer the questions. a. What do dolphins emit? b. What is echolocation? c. How does echolocation help dolphins to navigate? d. What else do dolphins use echolocation for? e. Have you ever heard sounds emitted by a dolphin? Where? 2 Search the Internet for information about another animal that uses echolocation. Complete the index card, including a picture. Echolocation Animal: Animal group: Use of echolocation: Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 65 Animals ASSESSMENT Name 1 Date Unscramble the letters and write the correct animal group for each photo. scadinirna shif 2 erpistel sgosnpe smowr closmuls samlamm rosphardot A B C D E F G H Tick (✓) the correct groups. mammals birds reptiles amphibians fish They are viviparous. They are oviparous. They breathe through lungs. They breathe through gills. They breathe through the skin. They have hair or fur. They have scales. They have feathers. They have bare skin. 66 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 3 Match. arthropodsTheir jelly-like bodies have poisonous tentacles. spongesThey have an articulated exoskeleton made of hard plates. 4 molluscs They have long, soft bodies with no legs. cnidarians Their sac-like bodies are full of pores. echinoderms Their skeleton is made of hard plates and spines. worms They have soft bodies and may have one or two shells. Read the sentences about arthropods and write the correct letter. I = insects A = arachnids C = crustaceans M = myriapods a. They have many identical segments. b. Most of them produce silk. c. They have eight legs and no antennae. d. They change through metamorphosis. e. They are the most abundant arthropods. f. Many have ten legs. 5 Find six parts of the insect. Photocopiable material © 2015 Santillana Educación, S.L. p h b w s e d g a t e f s z b o r b h a g e f a v g d o d q d p u w g o r x e h l m i a m a a n t e n n a e x m n p g a g t n c z t e s j s l z Natural Science 4 67 Animals TEST Name 1 Date The main groups of vertebrates are: a. primates, birds, crocodiles, amphibians and fish. b. mammals, birds, reptiles, amphibians and fish. c. cetaceans, songbirds, lizards, amphibians and fish. 2 Cetaceans are… a. fish. 3 c. primates. b. baby fish. c. baby amphibians. Fish and baby amphibians breathe through… a. lungs. 6 b. viviparous. Tadpoles are… a. baby reptiles. 5 c. aquatic mammals. Birds, reptiles, amphibians and fish are all… a. oviparous. 4 b. reptiles. b. the skin. c. gills. The main groups of invertebrates are: a. sponges, cnidarians, worms, snails, starfish and insects. b. sponges, cnidarians, worms, molluscs, echinoderms and arthropods. c. sponges, jellyfish, worms, octopuses, echinoderms and arachnids. 7 Mussels, snails and squids are all… a. molluscs. 8 c. arthropods. b. terrestrial animals. c. marine animals. Echinoderms are… a. vertebrates. 9 b. echinoderms. Arthropods include the following groups: a. insects, spiders, crustaceans and millipedes. b. insects, arachnids, crustaceans and myriapods. c. insects, scorpions, crabs and myriapods. 10 An insect’s body is divided into… a. head, segments and legs. b. antenna, thorax and legs. c. head, thorax and abdomen. 68 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Animals INVESTIGATE Name 1 Date How do you build a terrarium? Instructions 1. Work in groups. You need a clear plastic container, gravel, potting soil, small plants, snails, worms, ladybirds, ants or any other small animals collected in a nearby park, a magnifying glass and water. 2. Cover the bottom of the container with some gravel. Add some potting soil and put the plants in the soil. 3. Add enough water to the terrarium to make it moist. 4. Add the small animals you have collected and place the terrarium in a warm location with indirect sunlight. 5. Observe the terrarium over several weeks. Use the magnifying glass to look at the plants and animals. Record your observations and draw a picture every week in the table: week 1 week 2 week 3 week 4 observations picture Note: Make sure you add some water to your terrarium every week, but do not overwater! Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 69 Plants Name 1 REINFORCEMENT Date Label the parts of the plant. Then, match each part to its function. • T hey fix the plant to the ground and absorb water and other substances. • It supports the plant and transports water and other substances. • T hey make food for the plant. 2 3 Match the sentence halves about plant nutrition. Then, put them in order. a. Leaves take in water and mineral salts. b. Raw sap travels up and turns into elaborated sap. c. Elaborated sap is distributed carbon dioxide from the air. d. Oxygen is released the stem to the leaves. e. Roots absorb through the leaves. f. Raw sap mixes with carbon dioxide to all parts of the plant. Colour the arrows red for oxygen and blue for carbon dioxide. photosynthesis 70 Natural Science 4 respiration Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 4 5 Find the parts of the flower and label the diagram. Then, colour the female parts blue and the male parts red. g p e t a l i b i s c y e h a s k n s g t s t a m e n w t i s u p s o i l o v a r y p d z e l b g Unscramble the letters and label the pictures about asexual reproduction. retbu A 6 ziremho B C nolsot lubb D Read and match. mosses gymnosperms ferns angiosperms Photocopiable material © 2015 Santillana Educación, S.L. flowering plants non-flowering plants Natural Science 4 71 Plants EXTENSION Name Date Aquatic plants Most plants we know are terrestrial, in other words, they grow on land. However, there are also plants that grow in water. One of the most common aquatic plants is the water lily. This plant is found in calm freshwater habitats, such as ponds and lakes. Its large leaves and beautiful flowers float on the water. These are attached to underwater stems rooted to the bottom. Other aquatic plants, like the posidonia grow completely submerged in water. These plants with long, flat leaves are found in saltwater habitats. They cover large areas of the seabed, forming dense underwater meadows. They give food and shelter to many animals. 1 Read the text and complete the Venn diagram. water lily 2 aquatic plants posidonia Search the Internet for information about another aquatic plant. Complete the index card. Draw a picture. Aquatic plants Name: Description: Habitat: 72 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Plants EXTENSION Name Date Natural medicines For thousands of years, people have used plants for food, wood, clothes, perfumes and medicines. For example, hundreds of years ago, native American Indians used the bark of the willow tree to relieve pain. Nowadays, a substance is taken from the bark of this tree to make the well-known medicine called aspirin. There are many other examples of medicinal plants, but not many of them are used today because most medicines are made artificially in laboratories. However, we can still find natural medicines in people’s kitchens. For example, ginger and chamomile can help with digestion. Garlic and onions can help to fight infections. Peppermint can provide relief for colds, asthma and allergies. 1 Read the text and complete the sentences. a. Plants can be used for food, wood, clothes, perfumes and b. A substance from the . can relieve pain. c. Most modern medicines are made in . d. Some natural medicines are underground parts of the plant, such as ginger, garlic and . e. When you have an upset stomach, drinking f. When you have a cold, drinking 2 tea can help. tea can provide relief. Write the names and properties of natural medicines you have at home. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 73 Plants Name 1 ASSESSMENT Date Write T (true) or F (false). Then, correct the false sentences. a. Roots always grow underground. b. Stems can be herbaceous or woody. c. Trees and bushes have herbaceous stems. d. The petiole is the part of the leaf connected to the stem. e. Leaves are classified by the width of the leaf blade. f. Evergreen plants lose their leaves in autumn. 2 Circle the words about photosynthesis and label the diagram. carbondioxidewateroxygenmineralsaltssunlight 3 Write oxygen or carbon dioxide to complete the sentences. • During photosynthesis, plants take in during the day. • During respiration, plants take in during the day and at night. 74 Natural Science 4 and release and release Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 4 Complete the sentences about the reproduction of plants. Then, write a, b, c or d next to the drawings. germinates – seeds – pistil – stamens a. Pollen is formed in the . b. A grain of pollen reaches the flower. of another c. The ovary matures and turns into fruit. The fruit contains the . d. When a seed falls to the ground, it plant grows. 5 and a new Use the clues to complete the words about asexual reproduction. a. Specialized stems that grow horizontally underground. m b. Underground stems with leaves that store food. l c. Underground stems that develop roots. r d. Specialized stems that grow horizontally above the ground. 6 t Look at the photos and label the types of plants. mosses – angiosperms – ferns – gymnosperms A B Photocopiable material © 2015 Santillana Educación, S.L. C D Natural Science 4 75 Plants TEST Name 1 Date The main parts of a plant are… a. roots, stems and flowers. b. roots, stems and leaves. c. roots, branches and leaves. 2 Stems support the plant and… a. absorb water and other substances from the soil. b. perform photosynthesis. c. transport water and other substances to all parts of the plant. 3 Raw sap turns into elaborated sap with the help of… a. wind. 4 c. air. The process described above is called… a. respiration. 5 b. sunlight. b. nutrition. c. photosynthesis. During respiration, plants… a. take in oxygen and release carbon dioxide day and night. b. take in carbon dioxide and release oxygen day and night. c. take in oxygen and release carbon dioxide during the day. 6 The female part of a flower is the… a. stamen. 7 b. stamens. c. calyx. After pollination, the ovary matures and turns into a… a. bulb. 9 c. pistil. Pollen is produced in the… a. ovary. 8 b. corolla. b. new plant. c. fruit. Asexual reproduction uses structures such as stolons… a. rhizomes, bulbs and tubers. b. seeds, bulbs and tubers. c. rhizomes, flowers and tubers. 10 Plants are classified into two main groups… a. angiosperms and gymnosperms. b. flowering plants and non-flowering plants. c. mosses and ferns. 76 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Plants INVESTIGATE Name 1 Date Can you make a leaf collection? Instructions 1. Work in groups. You need some newspaper, large pieces of card, some glue and a magnifying glass. 2. Collect leaves from the playground, a nearby park or the countryside. 3. Press and dry the leaves by placing them in between pieces of newspaper with a heavy weight on top. Leave them for a week. 4. Once dried, classify the leaves by their edges and the shape of their leaf blades. Use the magnifying glass to look at the edges. Use this chart to classify them. simple leaves edge shape linear smooth lance-shaped jagged lobed needle-shaped heart-shaped round ovate palmate 5. Glue the different groups of leaves to the card and label them with their type of edge and their leaf shape. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 77 Wild plants and crops REINFORCEMENT Name 1 Date Write T (true) or F (false). Then, correct the false sentences. a. Plants need to grow in the right habitat to survive. b. All plants need the same amount of water. c. With no sense organs, plants cannot respond to changes in the environment. d. Most responses from plants are related to growth. e. Roots grow down towards water. f. Most plants can respond to touch. 2 Read and write annual or perennial. a. They have a long life cycle. b. Poppies and sunflowers are examples of these plants. c. They can be grasses, bushes or trees. d. They have a life cycle of one year. e. They can be deciduous or evergreen. 3 Unscramble the letters and label the photos of the different areas. setfro A 78 Natural Science 4 busndrahl B tedres C salrsdang D Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 4 Read the sentences and complete. desert – shrubland – forest – grassland 5 6 a. A is an area where many trees grow close together. b. A is an area dominated by grasses. c. A is an area dominated by bushes. d. A is an area with very few plants. Find five stages of crop farming. g p e t a l i t p h b i p c y h h s l z i r r i g a t i o n s t u m e r w b u v f e n t i v i z g n i l i v a e r c h e p d n e h s r v i s g e g v k t i r n p d b h d x i g b g d y t u l a n a c n b s o w i n g s o q g Cross the odd one out and write the type of crop. a. tomatoes lettuce olive trees potatoes b. wheat tomatoes barley olive trees c. fruit trees olive trees corn vines d. corn barley tomatoes rice e. vines plum trees rice pear trees Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 79 Wild plants and crops EXTENSION Name Date Seasonal fruits Some fruit trees produce fruit all year round, like banana trees. However, other fruit trees produce fruit at different times of the year. These trees need a particular temperature and humidity to grow and produce fruit. Therefore, some fruits are only produced in certain seasons, for example, melons are only produced in summer and grapes in autumn. Eating seasonal fruits has many advantages. Fruits in season taste better. They are cheaper and fresher since they travel directly from the fields to the markets. In addition, since they do not need to be stored or refrigerated, less energy is used. Therefore, eating fruits in season is better for the planet! 1 J F M A M J J A S O N D cherries pomegranates apples peaches melons oranges loquats bananas grapefruits grapes Read the text and the fruit calendar. Then, answer the questions. a. What are seasonal fruits? b. What are the advantages of eating fruits in season? c. Which fruits have the shortest season? d. Which fruits have the longest season? e. Why is eating fruits in season better for the planet? 2 Using the seasonal fruit calendar above, write two fruits you can eat for each of these months. March April May June 80 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Wild plants and crops EXTENSION Name Date The flowering desert The Atacama Desert is located along the Pacific coast in South America. It is the driest non-polar desert in the world. In some areas of this desert, it only rains every 5, 20 or even 400 years! So it is almost impossible for living things to survive. However, when it rains, an extraordinary event takes place between September and November, known as the flowering desert. Water from rainfall reaches the seeds and bulbs that have been underground for years. The seeds then germinate, grow and bloom at an incredibly fast rate. As a result, the desert gets covered with a beautiful carpet of flowers! 1 Put the words in order to make correct sentences. is South America the Desert Atacama in a. almost is living things survive to for impossible it b. 2 Complete the index card about the flowering desert. The flowering desert Description of the event: Location: Time of the year: Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 81 Wild plants and crops ASSESSMENT Name 1 Date Write a sentence with each group of words. light leaves stem towards grow a. respond changes environment plants b. plants growth water light need c. humidity roots in search of grow d. 2 Tick (✓) the correct boxes. annual plants perennial plants grasses trees and bushes Their trunks and roots grow throughout their life cycle. Their visible part disappears every year. Their seeds remain in the soil and grow new plants. Some of their organs remain underground. They grow in the spring and die in the summer. Their leaves can be deciduous or evergreen. They grow flowers and seeds in the spring. 82 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 3 Complete the sentences with the types of areas. a. can have many different types of trees. b. Cactuses grow in because they need very little water. c. Trees and bushes are scarce in d. After a very long time, 4 . can grow into forests. Write a definition of crop farming. 5 Read the descriptions and write the corresponding stage in the process of farming. ploughing – sowing – harvesting – pruning – irrigation – fumigation – fertilizing a. Placing seeds carefully in the soil. b. Spraying plants with pesticides to fight pests. c. Adding mineral salts to help plants grow. d. Collecting mature crops from fields. e. Turning the soil to make it ready for planting. f. Watering crops when rainfall is not enough. g. Cutting some branches from trees and bushes. 6 Write two examples of each type of crop. dry crops irrigated crops herbaceous crops trees and bushes Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 83 Wild plants and crops Name 1 TEST Date To carry out photosynthesis, plants need… a. sunlight, humidity, mineral salts and oxygen. b. heat, water, salt and carbon dioxide. c. sunlight, water, mineral salts and carbon dioxide. 2 Like animals, plants can… a. make their own food. b. respond to changes in the environment. c. move from place to place. 3 Depending on their life cycle, plants can be… a. trees or bushes. b. deciduous or evergreen. c. annual or perennial. 4 All the plants in an area, region or country are known as the… a. habitat. 5 b. vegetation. c. fauna. Forests need… a. high humidity and fertile soil. b. low humidity and arid soil. c. medium humidity and poor soil. 6 Grasslands are found in places with long periods of… a. rainfall. 7 c. drought. Most crops are used for… a. raw materials. 8 b. sunshine. b. food. c. animals. The first and last stages in the process of farming are… a. irrigation and pruning. b. sowing and fertilizing. c. ploughing and harvesting. 9 Dry crops only need… a. rainfall. b. water. c. irrigation. 10 Corn, tomatoes and rice are… a. irrigated crops. 84 Natural Science 4 b. herbaceous crops. c. dry crops. Photocopiable material © 2015 Santillana Educación, S.L. Wild plants and crops INVESTIGATE Name 1 Date What types of plants grow near your school? Instructions 1. Take a walk around your school and look for different plants growing there. 2. Use a magnifying glass to examine the different parts of each plant. 3. Complete the table with your observations. Use words and drawings. 4. Share your observations with the class. plant 1 plant 2 plant 3 tree, bush or grass deciduous or evergreen stem leaves flowers fruits Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 85 Matter and materials REINFORCEMENT Name 1 Date Write G (general properties) or S (specific properties) for each property of matter. colour taste 2 density hardness volume Read and match. mass volume 3 mass amount of space an object occupies amount of matter in an object cubic metres (m3) cubic centimetres (cm3) litres (l) and millilitres (ml) kilograms (kg) and grams (g) Look at the picture and tick (✓) the correct answers. a. What is the volume of this substance? 1 litre 1 kilogram 1 millilitre 1 kilogram 1 millilitre 1 g/l 1 g/cm3 water orange juice b. What is its mass? 1 litre c. What is its density? 1 cm3/g d. What substance is it? milk 4 Answer the questions. a. What instrument do we use to measure mass? b. What do we use to measure the volume of liquids? 86 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 5 Look at the photos and read the sentences. Write higher than or lower than, and circle the correct word. A a. The density of the brick is than the density of water. So it sinks / floats in water. B 6 b. The density of the leaf is than the density of water. So it sinks / floats in water. Circle the materials. Then, write each material next to its properties. lass metalsg plasticswoodtextilesoptica lfibre a. They are flexible, resistant and easy to work with. b. It is flexible and transparent. c. It is hard, transparent and fragile. d. They are heavy, ductile and malleable. e. They are light, cheap and easy to mould. f. It is light and easy to work with. 7 Write two properties of each material. A B C Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 87 Matter and materials Name EXTENSION Date Quiviut: the best wool in the world In the coldest regions of the Arctic lives an animal that looks almost prehistoric. Despite its name, the musk ox is more closely related to a sheep or a goat, than an ox. Musk oxen live in herds in the wild. Their bodies are covered with two thick layers of wool. The outer layer consists of long thick hair which reaches almost to the ground. The inner layer is made up of fine, soft, greyish-brown wool, called quiviut. Every spring, musk oxen lose their quiviut layer and grow a new one, so there is no need to shear them. Quiviut is considered one of the softest and warmest fibres in the world. In addition, it does not shrink like sheep’s wool when you wash it in hot water. 1 Read the text. Then, answer the questions. a. Where do musk oxen live? b. Which animals are considered their closest relatives? c. How do musk oxen survive in their extremely cold habitat? d. What is their outer wool coat like? e. What are the properties of quiviut? f. Why is quiviut considered better than sheep’s wool? 2 Search the Internet for information about four other animal fibres and complete. animal 88 Natural Science 4 fibre Photocopiable material © 2015 Santillana Educación, S.L. Matter and materials EXTENSION Name Date Amazing materials Nowadays, there are many new materials with amazing properties. Fibreglass is one of them. It is made of very thin threads, or fibres, of glass. When these glass fibres are woven together, they make a light, but strong and versatile material. Fibreglass is used to make many different objects, such as boats, surfboards and poles for pole vaulting. Fibreglass is also used to make optical fibre. This material is made of very fine fibres of pure glass. Light travels easily through them. Cables made of optical fibre can send information in the form of light from one side of our planet to the other. 1 Read the text and complete the index card. Fibreglass Composition: Properties: Uses: 2 Search the Internet for information about two new materials. Then, complete. name composition Photocopiable material © 2015 Santillana Educación, S.L. properties uses Natural Science 4 89 Matter and materials ASSESSMENT Name 1 Date Complete the text about matter. general – mass – volume – matter – space – substances – specific – density is everything around us that takes up . Objects are made of different types of matter called Matter has . properties that are common to all matter, like and . Matter also has that are different for each substance, like 2 . Complete the table about matter. definition mass is measured in the amount of matter in an object is measured with scales litres l or millilitres ml volume 3 properties Circle on the scales the ball with the highest density. Explain how you know. 90 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 4 Calculate the density of these objects. Then, answer the question. object A mass = 60 g volume = 30 cm3 object B mass = 30 g volume = 60 cm3 • Which of these two objects floats in water? Explain. 5 6 Find and write five properties of materials. r e s i s t a n t h l b i p c y h h s l z i a. i r h i g a e i o n g b. s t e m e r l p u v h c. t r a n s p a r e n t d. i l v v a e s r h e v e. p d y e h s t v i s w g e f l e x i b l e x d b h d x i c b g d y Cross the odd one out in each group. Then, write the new material. solar shade clothing fragile fire-resistant clothing waterproof breathable clothing a. bakelite concrete PVC neoprene b. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 91 Matter and materials TEST Name 1 Matter is everything around us that takes up… a. space. 2 c. always the same. b. scales. c. a measuring cylinder. b. cubic metre. c. kilogram. The concentration of matter in an object is the… a. volume. 6 b. different for each substance. There are 1,000 ml or 1,000 cm3 in a… a. litre. 5 c. mass. Mass is measured using… a. a thermometer. 4 b. volume. Mass and volume are… a. common to all matter. 3 Date b. mass. c. density. To calculate the density of an object, we need to… a. divide its volume by its mass. b. divide its mass by its volume. c. multiply its mass by its volume. 7 Objects float because their density… a. is equal to the density of water. b. is lower than the density of water. c. is higher than the density of water. 8 Wood, glass and pottery are not… a. good conductors of heat. b. good conductors of electricity. c. good conductors of heat and electricity. 9 Most plastics are made from… a. petroleum. b. minerals. c. sand. 10 Smart clothing for outdoor activities include… a. solar shade clothing and fire-resistant clothing. b. solar shade clothing and waterproof breathable clothing. c. waterproof breathable clothing and fire-resistant clothing. 92 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Matter and materials INVESTIGATE Name 1 Date Does it sink or float? Instructions 1. Work in groups. You need a large plastic container, a collection of small objects, such as a rock, an apple, an orange, a leaf, a metal spoon, a plastic spoon, a wooden spoon, a coin and some water. 2. You are going to test whether these objects sink or float. 3. First, write your predictions in the table: F (floats) or S (sinks). rock apple orange leaf metal spoon plastic spoon wooden spoon coin prediction result 4. Then, take turns placing the objects in the water. Record the results in the table. 5. Compare your predictions and results. 6. Classify the objects in this table. objects that float objects that sink 7. Write your conclusion. Circle. • The density of the objects that float is higher / lower than the density of water. • The density of the objects that sink is higher / lower than the density of water. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 93 Forces and energy REINFORCEMENT Name 1 Date Look at the pictures and write the effect of each force. Then, answer the question. A B C D • Are these forces acting through contact or from a distance? 2 Read the sentences about gravity and circle the correct words. a. Gravity pulls objects upwards / downwards. b. This force attracts / repels all objects towards the centre of the Earth. c. It acts by contact / from a distance. d. It cause the Moon / Mars to orbit around the Earth. 3 Circle the energy sources and classify them. Then, answer the question. oaluran c m u le naturalgaspetro iumsunlightwindflowingwater plant remains renewable energy sources non-renewable energy sources • What is the main difference between renewable and non-renewable energy sources? 94 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 4 Read the descriptions about energy sources and write renewable or non-renewable. a. They are available at any moment. b. They contribute to global warming. c. They will run out one day. d. They are continually produced in nature. e. They cause less pollution than fossil fuels. f. Some are easy to use in different machines, like fuel from petroleum. 5 Look at the photos and complete the table about the power plants. A B type of power plant C energy source energy transformation wind farm A natural gas, coal, petroleum fuels B energy from sunlight into electrical energy C 6 Use the colour key to circle the words about uses of energy. electrical energy ▶ red lamp energy from fossil fuels ▶ blue car aeroplane air conditioning industries Photocopiable material © 2015 Santillana Educación, S.L. refrigerator train radiator both ▶ green computer lorry Natural Science 4 95 Forces and energy EXTENSION Name Date Sir Isaac Newton The great British mathematician and physicist, Sir Isaac Newton, was born in England in 1624. He was often ill during his childhood and was not a good student at school. However, he studied at Cambridge University, and made many important discoveries in Mathematics. One of his greatest achievements was the discovery of the force of gravity. He made this discovery when he was sitting under an apple tree and an apple fell to the ground. He used Mathematics to explain his law of universal gravitation. He also studied the properties of light, and carried out many experiments about light and colours. 1 Read the text and complete the index card. Sir Isaac Newton Year and place of birth: University education: Main discovery: 2 Search the Internet for information about another famous scientist. Write an index card and include a picture. 96 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Forces and energy Name EXTENSION Date Energy from forests Forests need to be cleared in spring, before the arrival of summer. Forest maintenance includes removing fallen branches, pine cones, bark, tree trunks and any other dry vegetation. This helps to prevent forest fires. All this forest debris can be used to make biomass. Biomass is organic matter, especially from plants, that can be converted into fuel. Biomass is a renewable source of energy that can be used to heat water and homes. In addition, it can also be used to produce electrical energy. In Spain, for example, the large amounts of olive stones discarded from olive oil production are used for biomass to produce thermal energy. 1 Read the text and answer the questions. a. Why is it important to clear forests? b. At what time of year are forests cleared? Why this season? c. What can forest debris be used for? d. Is biomass a renewable or non-renewable energy source? e. Which forms of energy can be obtained from biomass? f. Which plant debris is used as biomass in Spain? 2 Search the Internet for more information about biomass. Write two advantages and two disadvantages. • Advantages: • Disadvantages: Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 97 Forces and energy ASSESSMENT Name 1 Date How is the force acting in each situation? Match. a. A girl riding a bike b. A pencil falling to the ground from a distance c. A woman pushing a pushchair through contact d. A magnet attracting a metal ball 2 Look at the picture. Complete the text about the force acting on each person. The force acting on these people is . This force attracts all objects towards the of the 3 . It acts from a . Circle six energy sources. Then, complete the sentences with the words. g p e t r o l e u m p l i p c y h h s l s u n l i g h t i o d t t o m e r w d w b o q n t i v i z i e n u r v c e r t n f i r e w o o d v d j u e g v a t i r n a m b h d l i g b g a. This fossil fuel is used to produce petrol, oil and plastics. 98 b. This renewable energy source comes from plants. c. This non-renewable energy source is a nuclear fuel. d. This renewable energy source is not available at night. e. This fossil fuel is used directly as fuel. f. This renewable energy source makes machines work. Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 4 Read the sentences about energy sources and tick (✓) the correct boxes. renewable energy sources advantage disadvantage non-renewable energy sources advantage disadvantage They will never run out. They can be easily stored and transported. They cause lots of pollution. They are not continually available. They will run out one day. They are difficult to use directly. 5 6 Match. power plant energy sourceenergy transformed into electricity wind farm fossil fuels mechanical energy nuclear power plant flowing water chemical energy hydroelectric power plant nuclear fuels light energy thermal power plant sunlight nuclear energy solar power plant wind Write two uses for each form of energy. • Electrical energy: • Chemical energy from fossil fuels: Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 99 Forces and energy TEST Name 1 When pushing or pulling on an object, we apply… a. movement. 2 Date b. force. c. energy. Forces can change… a. the shape of an object. b. gravity acting on an object. c. the composition of an object. 3 We stay on the ground because of… a. magnetism. 4 b. weight. c. gravity. Non-renewable energy sources include… a. fossil fuels and nuclear fuels. b. petroleum and plant remains. c. coal, sunlight and plutonium. 5 Non-renewable energy sources can be easily stored and… a. transformed. 6 b. produced. c. transported. Renewable energy sources are… a. continually produced in nature. b. only sometimes available. c. running out very quickly. 7 Firewood is a… a. renewable energy source. b. non-renewable energy source. c. a very polluting energy source. 8 Aeroplanes and cars transform chemical energy from fuels into… a. light energy. 9 b. electrical energy. c. mechanical energy. Hydroelectric power plants use mechanical energy from… a. wind. b. sunlight. c. flowing water. 10 The most common forms of energy we use are… a. electrical energy and chemical energy. b. light energy and mechanical energy. c. thermal energy and nuclear energy. 100 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Forces and energy INVESTIGATE Name 1 Date How much energy do you use? Instructions 1. Work in pairs to complete this survey. 2. Ask a partner the questions and circle their answers. Then, exchange roles and answer your partner’s questions. Survey 1. Do you turn off the lights when not in use? a. Always. 2. b. Almost always. Do you turn off the tap while brushing your teeth? a. Always. 3. c. Hardly ever. b. Almost always. c. Hardly ever. What do you do with an appliance that does not work? a. I bring it to the shop to be repaired. b. I bring it to the recycling centre. c. I throw it away. 4. What objects do you recycle? a. Plastic, paper and glass. 5. b. 15 ºC. c. 30 ºC. Do you have a daily bath or a shower? a. A shower. 2 c. None. At which temperature do you set the thermostat at home? a. 22 ºC. 6. b. Plastic and paper. b. It depends. c. A bath. Count the number of ‘A’ answers in your survey. Give your partner a score. 1 to 2 ‘A’ answers = You need to take action! 3 – 4 ‘A’ answers = There is room for improvement. 5 – 6 ‘A’ answers = Well done!!!! Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 101 Forces and movement Name 1 REINFORCEMENT Date Look at the photos and write the effects of the forces. changes the shape – makes the object break – makes the object start/stop moving A B C 2 Read and complete the text. An object at rest will not move unless a acts upon it. In contrast, when an object is in motion it will continue to move until a force makes it or 3 . Calculate the speed. Answer the questions. a. How many km will he travel in one hour? Sam cycles 8 km in 30 minutes. b. At what speed is he travelling? 102 8 km/h 4 km/h 16 km/h 32 km/h Natural Science 4 0 km 8 km Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 4 Read the sentences and tick (✓) the correct boxes. friction gravity It is a contact force. It pulls objects downwards. It causes the Moon to orbit the Earth. It slows down moving objects. It acts from a distance. It attracts all objects towards the centre of the Earth. It happens when two objects rub against each other. 5 Look at the pictures and answer the questions. A B C a. In picture A, what makes the ball start moving? b. What do the arrows represent? c. Why do the arrows get smaller in each picture? 6 Read and write T (true) or F (false). a. Speed tells us how fast something moves. b. Gravity only affects objects moving downwards. c. Friction makes objects slow down. d. Gravity decreases the speed of a falling object. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 103 Forces and movement Name EXTENSION Date Friction in sports Friction is the force that slows down the movement of an object when it is in contact with a surface or another object. Surface friction affects sports which involve a ball, a wheel or skis sliding across a surface. Friction differs depending on the surface: the smoother the surface, the less friction there is. In some sports, such as skiing or ice skating, it is an advantage to reduce friction as much as possible. Skis are treated with wax so they slide faster. Skate blades are very sharp in order to reduce friction. However, in some sports it is an advantage to increase friction. For example, in football and in golf, players wear shoes with studs so they do not slip. 1 Read the text and answer the questions. a. When does friction occur? b. Is friction greater on ice or on a football pitch? c. Why do skiers put wax on their skis? d. When friction is reduced, does a skier go faster or slower? e. Write some sports where it is an advantage for the players to have increased friction. 2 104 Search the Internet to find out how friction affects another sport. In your notebook, write a short text about whether friction is increased or reduced to gain advantage. Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Forces and movement EXTENSION Name Date The Maglev In April 2015, the Japanese Maglev train reached a record speed of 590 km/h! The name Maglev comes from the combination of two words, magnetism and levitation. Levitation is the hovering of an object in the air, and magnetism is the force of attraction and repulsion between magnets. These two forces help the Maglev train to reach maximum speed in the following way: Magnets have two different poles. Opposite poles attract each other and like poles repel each other. The Maglev train has powerful magnets instead of wheels. It sits on a track with magnets. Like poles are facing each other, therefore the magnets repel each other. The train levitates about 10 cm above the track. In this way, friction against the track is eliminated and the train reaches record speeds. 1 Read the text. Then, answer the questions. a. Which force acts against the movement of a normal train? b. Does this force completely disappear in a Maglev train? Explain. c. What makes the train levitate? d. Does magnetic force work through contact or from a distance? 2 Draw arrows showing the forces between the magnets and circle the picture of the magnets corresponding to a Maglev train. Then, answer the question. • What would happen to the Maglev train if opposite poles were facing each other? Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 105 Forces and movement ASSESSMENT Name 1 Date Draw a picture for each effect of forces. A Forces make objects change their shape. 2 B C Forces make objects break. Forces make objects start moving. Look at the picture and draw arrows to show the forces acting on the rope. Then, complete the sentence. • When the same is applied in directions, the objects do not move. 3 Write T (true) or F (false). Then, correct the false sentences. a. Forces can act through contact or from a distance. b. Magnets attract metal objects when they are in contact. c. Friction is a force which acts from a distance. d. Friction always slows down moving objects. e. Water resistance is the friction of an object against water. f. When objects move through the air, there is air resistance. 106 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 4 How do objects change shape when a force acts on them? Write permanent change, temporary change or breaks. 5 Colour the words related to friction in blue, and the words related to gravity in red. contact centre of the Earth fall slow down distance downwards resistance rub 6 Draw arrows to show movement and the force of friction. Then, solve the problem. If the car travels 300 kilometres in 4 hours, what is its speed? 7 Draw red arrows to show the force of gravity and blue arrows to show the movement. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 107 Forces and movement TEST Name 1 Forces can make objects… a. change shape or break. 2 Date b. start or stop moving. c. both A and B. When applying enough force to rigid objects… a. they change their shape temporarily. b. they change their shape permanently. c. they bend. 3 When a force acts upon a moving object,… a. it always makes the object stop. b. it always makes the object change direction. c. it makes the object stop or change direction. 4 Most forces are… a. contact forces. 5 b. friction. c. gravity. When an object moves against a liquid or a gas, there is… a. gravity. 7 c. magnetic forces. The force that slows down a moving object is called… a. magnetism. 6 b. non-contact forces. b. resistance. c. friction. To calculate speed, we… a. divide the time it took to travel a distance by the distance. b. multiply the distance travelled by the time it took to travel this distance. c. divide the distance travelled by the time it took to travel this distance. 8 If a car travels at 120 km/h, how long will it take to travel 240 km? a. three hours 9 b. two hours c. four hours When the force of pedalling is greater than the force of friction, the speed of a bike… a. increases. b. remains the same. c. decreases. 10 Gravity affects… a. only objects moving downwards. b. only objects moving upwards. c. objects moving downwards and upwards. 108 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Forces and movement Name 1 INVESTIGATE Date How is friction affected by different surfaces? Instructions 1. Work in groups. 2. You need a shoe box, a towel, a sheet of bubble wrap, a sheet of wax paper, a pencil, tape and glue. 3. Make a ramp using the lid of the shoe box. 4. Place the pencil at the top of the cardboard ramp. Observe how fast it rolls down. 5. Put the towel on the ramp and repeat the experiment. 6. Repeat the experiment twice more: first with the wax paper placed on the ramp, and then with the bubble wrap placed on the ramp. 7. Now, complete the sentences. a. The pencil rolls down faster on . b. The pencil rolls down slower on . c. Friction is greater on a surface made of . d. Friction is reduced on a surface made of . 8. Make your conclusions. Circle. • The smoother the surface, the more reduced / greater the friction. • The rougher the surface the more reduced / greater the friction. 9. Compare your conclusions as a class. 10. Think of other different surfaces you can try out on your ramp. Try them out with your group. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 109 Heat and light REINFORCEMENT Name Date 1 How does heat transfer from one object to another? Colour the correct arrows in red. 2 Circle the materials and classify them. Then, answer the question. irong la lassp s gold s c i t woodwaterceram conductor ics alum inium insulator • Which materials can you use to make a saucepan? 3 Write transparent, translucent or opaque for each container. A 110 Natural Science 4 B C Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 4 Read and write refraction or reflection. a. Light passes from one material to another. b. Light can make objects appear to change size and shape. c. Light bends and changes direction. d. Light bounces off and changes direction. e. This allows us to see everything. f. This happens best on smooth, shiny surfaces. 5 Write T (true) or F (false). a. White light can be separated into six colours. b. The primary colours of light are red, green and yellow. c. When we mix red, green and blue light, we can make many colours. 6 Colour each object in its corresponding colour. a. It absorbs all colours of light, but reflects red light. b. It does not absorb any colour of light, but reflects all of them. c. It absorbs all colours of light, but reflects yellow light. d. It absorbs all colours of light. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 111 Heat and light EXTENSION Name Date Our Sun: a natural source of light and heat Like other stars, our Sun shines so brightly because it is extremely hot. The centre of the Sun can reach up to 15 million degrees Celsius. It produces energy in the form of light energy and thermal energy. This energy takes between 10,000 and 150,000 years to reach the surface of the Sun from its core. This enormous star is made up of mainly two gases, hydrogen and helium. When hydrogen combines to make helium, huge amounts of light and heat are released. As a result, the mass of the Sun is being consumed at a very slow rate. In about 5 billion years, our Sun will start to die. 1 Read the text and answer the questions. a. How hot is the centre of the Sun? b. What forms of energy does the Sun produce? c. How long do they take to reach the surface of the Sun? d. What gases is the Sun made up of? e. How does the Sun produce light and heat? f. Is the Sun going to last forever? Explain 2 Search the Internet for more information and pictures of our Sun. Print out two photos, cut them out, paste them in the boxes and write a sentence under each photo. 112 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Heat and light Name EXTENSION Date Shadows People are fascinated by shadows because we can never catch them nor touch them. But what is a shadow? It is the dark area caused when an object blocks light. To make a shadow, an object must be opaque or translucent. Shadows from opaque objects are darker than shadows from translucent ones. Transparent objects do not make shadows because they allow all the light to pass through. Shadows can change size and shape. Indoors, they get bigger as you move closer to a light source, and they get smaller when you move away from the light source. Outdoors, shadows change as the position of the Sun in the sky changes. 1 Read the text and answer the questions. a. What is a shadow? b. Do all objects produce shadows? Explain. c. Which objects produce the darkest shadows? d. How do shadows change indoors? e. How do shadows change outdoors? 2 Search the Internet for images of hand shadows. Practise them and teach your classmates. Draw your favourite hand shadow. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 113 Heat and light Name 1 ASSESSMENT Date Read and write heat or temperature. a. It is measured with a thermometer. b. It causes changes in materials. c. It refers to how cold or hot an object is. d. It is measured in degrees centigrade. e. It is the transfer of thermal energy between objects. 2 Read the sentences and circle the correct word. Then, match the pictures to the correct sentences. a. Conductors / insulators transmit heat very well. b. Heat makes the shape / temperature of an object increase. c. When the temperature of an object decreases / increases, it can cause dilatation. d. Expansion joints allow bridges to expand / contract when their temperature increases. e. Substances can change state when they transfer / change temperature. 3 Tick (✓) the properties of light. a. Light allows us to see everything around us. b. Light travels very slowly. c. Light comes from man-made sources. d. Light travels in all directions. e. Light is a form of energy. f. Light travels in a curved line. 114 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 4 Use the words to write a sentence about each picture. refraction bends direction A light reflection bounces off B a. b. 5 Colour and complete the diagram of the primary colours of light. Then, answer the question. • Which are the primary colours of light? Explain. GREEN RED BLUE 6 Write and draw an example for each case. a. An object that absorbs all colours of light: b. An object that reflects all colours of light: Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 115 Heat and light TEST Name 1 Ice cubes in a jug with water melt because the water transfers… a. heat. 2 c. degrees centigrade. b. water. c. iron. b. plastic bowl. c. metal bowl. Shadows form because light travels… a. in all directions. 6 b. kilograms. Ice melts faster in a… a. glass bowl. 5 c. temperature. Examples of insulators are plastic, glass and… a. wood. 4 b. thermal energy. Temperature is measured in… a. degrees. 3 Date b. very fast. c. in a straight line. Objects appear blurry when seen through… a. transparent objects. b. translucent objects. c. opaque objects. 7 Refraction happens when… a. light bends as it passes from one material to another. b. light reflects and changes direction. c. light travels in a straight line. 8 The primary colours of light are… a. red, yellow and blue. b. green, yellow and blue. c. red, green and blue. 9 Objects can be seen because of the… a. dispersion of light. b. reflection of light. c. refraction of light. 10 An object that absorbs all the colours of light appears… a. white. 116 Natural Science 4 b. transparent. c. black. Photocopiable material © 2015 Santillana Educación, S.L. Heat and light Name 1 INVESTIGATE Date Does light travel in a straight line? Instructions 1. Work in groups. You need card, some plasticine, a hole puncher, some scissors and a torch. 2. Cut out four squares of card. Use the hole puncher to make a hole in the centre of three of the squares. 3. Use the plasticine to make four bases to stand the squares of card in. 4. Place the cards in a straight line with the holes aligned. Put the card with no hole at the end. Your experiment will look similar to the photograph. 5. Shine the torch through the hole in the first card and observe the last card. 6. Now, move the second or third card slightly out of line. 7. Shine the torch again through the hole in the first card and observe the last card. 8. Write a conclusion. • When the holes in the cards are aligned / not aligned… Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 117 Machines REINFORCEMENT Name 1 Date Unscramble the letters. Then, label the pictures. necdilninepal 2 118 revel lylupe Write the type of lever in each picture. A 3 B C Circle the complex machines. Then, tick (✓) the ones that work with electricity. Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. REINFORCEMENT 4 Look and write the components of these complex machines. operating part – switch – control component – indicator 5 6 Match the words to the definitions. a. belts and chains It is a rotating disc with or without teeth. b. levers They transmit movement from one wheel to another. c. wheel It is a rod used to support wheels or gears. d. axle They produce movement. e. gears They transmit force. Use the correct words from activity 5 to label the picture. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 119 Machines EXTENSION Name Date Levers over time Did you know that our arms are levers? Yes, these simple machines are as old as human beings. However, animals were the first to make use of levers. Sea otters use rocks to open seashells, and orangutans use sticks to open fruit. Human beings also used objects as levers for these simple tasks. Later, they started to use trees as levers to move heavy rocks. Ancient Egyptians used levers to build pyramids and to draw water from rivers. Later in Ancient Greece, Archimedes wrote the Law of the Lever, which explains how levers work. Ancient Rome found new uses for levers: Romans used scissors to make clothing, and catapults to fight enemy armies. Nowadays, we use objects as levers in many different ways, for example, a hammer to bang in a nail, a bottle-opener to open a bottle, or a screwdriver to take the lid off a tin of paint. 1 Complete the timeline to show the history of levers. Ancient Egypt 2 Ancient Rome Search the Internet for examples of how we use levers nowadays. at school 120 Ancient Greece Natural Science 4 at home in the playground Photocopiable material © 2015 Santillana Educación, S.L. Machines EXTENSION Name Date A dizzy race A Formula 1 car is a very complex machine. It is made up of thousands of pieces. A fuel engine moves the gears, belts and chains. These parts transmit the movement from the engine to the wheels. The wheels then move the car. In addition, electric and electronic circuits allow the driver to check the car’s functions, for example, how much fuel is left. Driving a Formula 1 car is not easy. The driver of the car has to face intense forces that push him against the seat, or shake him about when he drives very fast round corners. Most Formula 1 drivers wear a neck protector to soften the effect of these forces. 1 Read the text and answer the questions. a. What type of machine is a Formula 1 car? b. Which operating parts transmit the movement from the engine to the wheels? c. What types of components allow the driver to know how much fuel is left? d. What protection do most drivers use? Why? 2 Search the Internet for information about three Formula 1 Grands Prix. Complete the table. Formula 1 Grand Prix Photocopiable material © 2015 Santillana Educación, S.L. country dates held number of races Natural Science 4 121 Machines ASSESSMENT Name 1 Date Use the key to colour the words about simple machines. Then, write a sentence about each machine. pulley ▶ red wheel axle pulley lever inclined plane inclined plane ▶ blue rope ramp lever ▶ green rigid bar 2 Draw and label pictures of a pulley, a lever and an inclined plane. 3 Write more or less to complete the sentences. a. Lifting an object with a pulley requires fulcrum effort than lifting the object without it. b. Lifting an object straight up requires force than pushing it up a ramp. c. When a force is applied to the long end of a lever, the short end moves distance, but it exercises 122 Natural Science 4 force on the object. Photocopiable material © 2015 Santillana Educación, S.L. ASSESSMENT 4 Use the clues to complete the components of complex machines. a. It protects the machine. v b. They control how the machine works. t m n c. It supports the other components. c d. They transmit movement. r t e. They give information about the functions. n c f. It produces movement. 5 and t 4 Complete the crossword about types of operating parts. Then, answer the questions. 3 ACROSS 2 1. They transmit force and can multiply it or reduce it. DOWN 2. Rods used to support wheels or gears. 3. Rotating discs with or without teeth. 1 4. They transmit movement from one wheel to another wheel. • What are wheels and axles working together called? 6 Draw arrows on the gears to show in which direction they will turn. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 123 Machines TEST Name 1 Pulleys, inclined planes and levers are… a. old machines. 2 b. complex machines. c. simple machines. We use our body weight when using… a. a lever. 3 Date b. a pulley. c. an inclined plane. The force required to move an object up a ramp depends on… a. the length of the ramp. b. the height of the ramp. c. the shape of the ramp. 4 A seesaw is a… a. first-class lever. 5 b. second-class lever. c. third-class lever. Complex machines are different from simple machines because… a. they need electricity or fuel to work. b. they are made up of a single complex part. c. they perform more complex tasks than simple machines. 6 The components of a complex machine involved with movement are… a. the operating parts and the motor. b. the screens and indicators. c. the cover and the control components. 7 Switches are used to… a. give information about the machine. b. control the machine. c. protect the machine. 8 The operating parts of a complex machine are the… a. rotating pieces. 9 b. moving pieces. c. electronic pieces. b. levers. c. belts. Gears are examples of… a. mechanisms. 10 Two wheels on the same axle or two wheels and a belt… a. turn in different directions. b. turn at different speeds. c. turn in the same direction. 124 Natural Science 4 Photocopiable material © 2015 Santillana Educación, S.L. Machines INVESTIGATE Name 1 Date How do gears work? 5 cm 5 cm 1. Work in groups. You need: a cardboard box 15 - 20 cm wide, some card, two barbecue skewers, a ruler, a compass, some scissors and glue. Cut out 6 wheels: two 8 cm diameter, two 5 cm diameter and two 2 cm diameter. 2. Push each skewer through the centre of three wheels. The first skewer represents the motor axle. Leave 5 cm between each wheel. Leave 4 cm between each wheel on the secondary axle. 2 cm Instructions 5 cm 8 cm Make a model of a gearbox to see how gears work. motor axle 4 cm 4 cm 3. Fix the wheels to the axles with a drop of glue. Then, glue a strip of card to one end of each axle. 4. Cut the sides of the box as shown in the picture. Push the axles through the sides of the box and fix with a piece of card. secondary axle 5. Move the axles to make two wheels coincide. In this way, a wheel from the motor axle will turn the secondary axle. You now have a gearbox with three gears. 5c m 5c m 3 cm First gear. The small wheel of the motor axle engages with the large wheel of the secondary axle. Second gear.The medium wheels of each axle engage. Third gear. The large wheel of the motor axle engages with the small wheel of the secondary axle. 6. Try out the gears. Decide if the secondary axle moves faster or slower than the motor axle for each gear. Photocopiable material © 2015 Santillana Educación, S.L. Natural Science 4 125 NOTES NOTES Art director: José Crespo Design coordinator: Rosa Marín Design team: Cover design: Estudio Pep Carrió Cover photograph: Leila Méndez Design development coordinator: Javier Tejeda Design development: Raúl de Andrés and Jorge Gómez Art coordination: Carlos Aguilera Technical director: Jorge Mira Technical coordinators: Marisa Valbuena Layout: Eva Hernández and Sandra Fernández Photo research: Nieves Marinas and Marilé Rodrigálvarez Photographs: ARCHIVO SANTILLANA All rights reserved. No part of this work may be reproduced, stored in retrieval system or transmitted in any form, electronic, mechanical, photocopying or otherwise without the prior permission in writing of the copyright holders. Any infraction of the rights mentioned would be considered a violation of the intellectual property (Article 270 of the Penal Code). If you need to photocopy or scan any fragment of this work, contact CEDRO (Centro Español de Derechos Reprográficos, www.cedro.org). © 2015 by Santillana Educación, S. L. / Richmond Publishing Avda. de los Artesanos, 6 Tres Cantos. 28760 Madrid Richmond Publishing is an imprint of Santillana Educación, S. L. Printed in Spain CP: 660744 ISBN: 978-84-680-2898-9 D.L.: M-39245-2015 Richmond Publishing 58 St Aldates Oxford OX1 1ST United Kingdom