Cambridge Primary Ready to Go Lessons for Science Stage 6 Answers to photocopiable pages Unit 1A: 6.1 Human organs and systems Page 12: Where are the major organs in our bodies? Page 9: Body organs lungs heart heart liver liver kidneys lungs brain kidneys Page 10: Organs in a small mammal lung heart Page 14: The brain and central nervous system liver stomach kidney 2. The organs are in a similar position to those in a human and some look similar. 1. Control centre for the body. 2. By nerves. 3. Sense organs have special cells called sensors. These respond to stimuli and send messages to the brain via the nerves. The brain recognises the stimulus, interprets the message and sends messages via the nerves to respond to the stimulus. 4. Brain, nerves and spinal cord. 1 Cambridge Primary Ready to Go Lessons for Science Stage 6: Answers to photocopiable pages Page 15: The brain 1. a) The brainstem is also known as the medulla. It connects the brain to the spinal cord. It is responsible for breathing, digestion and circulation. It is concerned with involuntary muscle action, for example the heart and in digestion. It sorts messages to and from the brain. b) The cerebellum is also called the little brain. It is concerned with balance, movement and co-ordination. It is also associated with emotions and learning. c) The skull is the bony protection inside which the brain is situated. 2. 1. a) muscle b) pump c) blood body d) Arteries e) Veins f) heart lungs g) body Page 22: Investigating pulse rate 1 1. running (though hopping or skipping could also be correct) taste touch Page 20: The heart and circulatory system skull smell sight hearing cerebellum 2. Answers will vary, for example: After exercise you are conscious of your raised heart beat. You can hear your heart beating and are out of breath. Running is the activity on this list that will make this happen most. 3–6. Personal response. brainstem Page 23: Investigating pulse rate 2 Page 17: Looking after our brain 1. Pictures should include lots of fish and vegetables. 2. Answers will vary, for example cycling, horseriding, baseball, American football, skiing. Personal response. Page 25: The lungs 1. bronchial tubes trachea (windpipe) 3. Answers will vary, for example reading, doing puzzles, playing a sport or musical instrument. 4. Rest / sleep. Page 19: Where is my heart? 1. lungs 2. Oxygen (O2). 3. Carbon dioxide (CO2). 4. Gaseous exchange. 2. To pump blood around the body. 2 Cambridge Primary Ready to Go Lessons for Science Stage 6: Answers to photocopiable pages Page 26: The respiratory system 1. trachea (windpipe) lung 2. Answers will vary, for example: The apple begins its journey in your mouth, where saliva begins to break it down. It travels down the food pipe and into the stomach, where it is churned up and broken down by stomach acid. The liver produces bile to aid digestion. The broken-down apple then passes into the small and large intestines where nutrients from it are absorbed into the body. Any remaining waste matter is passed through the rectum and out through the anus. Page 31: The excretory (urinary) system bronchus 1. kidneys ribs diaphragm 2. It goes from the lungs, up the trachea and out through the mouth. ureter 3. Respiration. Page 28: The digestive system bladder 1. mouth food pipe stomach intestines 2. To purify and clean the blood and / or produce urine. Page 32: The excretory (urinary) system Answers will vary, for example: Drink plenty of water: Water allows your kidneys to function properly and filter everything they need to. Eat a balanced, healthy diet: Eating the right foods means that your kidneys will have less work to do. rectum 2. Saliva 3. Food is churned up and broken down by stomach acid into liquid. Page 29: The digestive system 1. food pipe mouth stomach liver large intestine small intestine rectum anus Do not drink alcohol or smoke: Smoking and drinking alcohol means that your kidneys have to work harder to remove toxins from your blood. Page 34: Organs and systems wordsearch a s b t c u d v e w h m a j o r x f y g e h z l r a j b k c a l d m g e e f g l r o c s a f v e k u t u f u n c t i o n b r a i n o d e l g k o r t u n l o r s s t d i e m y r s g o l s y s e m e h t 3 Cambridge Primary Ready to Go Lessons for Science Stage 6: Answers to photocopiable pages Page 36: Organs and systems game The learners play the game as described on the photocopiable page. Page 37: Organs and organ systems Organ Organ system brain – central nervous Function – carries messages and acts as the control centre heart – circulatory – pumps blood around the body kidneys – urinary – removes waste stomach – digestive – breaks food down lungs – respiratory – exchange of gases Page 38: Where are the major organs? 1. brain 2. Answers will vary, for example: An ice-cube is solid. When it gets warm or is heated, it begins to melt and turn into liquid. This liquid is water. When water is heated it turns into a gas called water vapour and evaporates into the air. Page 43: Irreversible changes – making a clay pot The learners follow the instructions to make a coiled clay pot or a pinch pot, with help. Page 44: Irreversible changes – baking cakes The learners follow the recipe to make cakes, with help. Page 45: Irreversible changes 1. a candle burning and a fire burning 2. When cakes are baked, the ingredients combine to make something different – a new product that is unlike the original ingredients, which cannot be recovered. Page 47: Burning 1. lung heart Before Paper flat, smooth sheet Wood rough log kidney After grey ash small pieces of charred / black wood and ash 2. In any order: coal, oil, natural gas. 3. Answers will vary, for example: for cooking, transport and heating homes. 4. Food. Page 49: Observing a candle burning 2. Answers will vary, for example: Organ liver stomach intestines bladder Function Produces bile to aid digestion. Churns up and breaks food down. Absorb nutrients into the body. Stores urine. Look for descriptions including such words as wax, flame, burn, light, melt, drip, hot, run, soot, blue, yellow, sparks. Page 51: Separating solids 1–3. Personal response. 4. a) By hand. Page 39: A healthy heart b) Sieving. Personal response. c) Using a magnet. Unit 1B: 6.2 Reversible and irreversible changes Page 53: Mixing solids with water 1 Page 41: Reversible changes Personal response. 1. a) chocolate solid b) mouth melt Page 54: Mixing solids with water 2 c) runny liquid 1–3. Personal response. 4 Cambridge Primary Ready to Go Lessons for Science Stage 6: Answers to photocopiable pages 4. A mixture of a soluble solid and an insoluble solid can be separated by mixing them with water so that the soluble solid dissolves. Filter the remaining solution to separate the insoluble solid. Evaporate the water from the dissolved solid to recover the original solid. 5. Personal response. Page 56: Soluble or insoluble? 1–2. Personal response. 3. Accept answers that describe how the solid seems to disappear, but is still in the solution, dissolved in the water. Pages 69–70: Separating different mixtures 1 & 2 1. Soil and debris are making the water dirty. 2. You can get the salt out as crystals using evaporation. 3. Sieving will separate the soil. Evaporating, filtering and sieving have been used. Page 72: Interpreting results: melting ice-cubes 1. Place A. Pages 58–59: Observing mixtures 2. It was at 20 °C – the hottest room temperature. Answers will vary, according to the mixtures prepared or tested. 4. Answers will vary; check for correct use of data in drawing the graph. Page 61: Separating a complicated mixture 1 3. 10 °C. Page 73: Separating mixtures 1. a) magnetism The learners decide on a team name and allocate roles. b) by hand Pages 62–63: Separating a complicated mixture 2 & 3 d) filtration Look for evidence of sieving, filtering and evaporation in the method. Page 64: Separating a complicated mixture 4 Results Personal response. Conclusion Sieving would separate the rock salt. Mixing with water would dissolve the sugar. Filtering would separate the sand. Evaporation would produce sugar crystals. c) sieving e) evaporation f) sieving and evaporation 2. A sieve. 3. A magnet. 4. An evaporating dish and a heat source. Page 74: Reversible or irreversible? Change Reversible? Irreversible? water boiling ✓ a candle burning ✓ chocolate melting ✓ an egg cooking ✓ water freezing ✓ a fire burning ✓ Pages 66–67: Do solids dissolve quicker in hot water? 1 & 2 Unit 2A: 6.3 Food chains 1–4. Personal response. Page 76: Energy source 5. spoons / spatulas / weighing scales 1. Personal response. 6. a thermometer 2. Answers will vary; look for good sources of fat, sugar, carbohydrates or proteins. 7. stopwatch / clock / timer Results Personal response. Conclusion The hotter the water, the quicker / faster the solid dissolved. 3. Answers will vary, according to the foods chosen. 4. The Sun. Page 78: Food chains 1. Answers will vary, for example: or Meat-eater The cooler the water, the slower the solid dissolved. grass → chicken → human 5 Cambridge Primary Ready to Go Lessons for Science Stage 6: Answers to photocopiable pages Vegetarian Page 92: Prey spinach → human 1–2. Personal response. 2. Both food chains begin with a green plant. Page 79: Drawing and writing food chains 1. leaf → caterpillar → bird → snake 2. green plant → gazelle → lion 3. The flow of energy. Page 81: Producers 1. Answers will vary, for example: 3. no Pages 94–95: Predators and prey 1 & 2 The learners play the game as described on photocopiable page 94. Page 97: Food chains in the desert 1–2. Answers will vary, for example: → ant → a) leaves cactus b) grass producer → primary → consumer c) corn 2. green plants Pages 83–84: Consumers Resources for the page 82 Starter activity game. Page 85: Consumers 1. a) bird secondary consumer Page 98: Food chains in a mountain environment 1. snow leopard 2. a) moss b) mountain goat c) snow leopard b) goat d) mountain goat c) antelope 2. Personal response. Page 87: Secondary consumers 1. Answers will vary, for example wolf. producer → primary → secondary consumer consumer Page 99: Food chains in the ocean 1. seaweed 2. shark 3. killer whale (Orca) 4. primary consumer 3. Personal response. Page 88: Tertiary consumers 1. Answers will vary, for example whale. 2. a) Sun 5. Answers will vary, for example plankton, algae. Page 100: A tree as a habitat Answers will vary, for example: b) green plant 1. palm tree c) herbivores d) herbivores snake carnivores e) omnivores Page 90: Predators 1. small insect millipede bird → 2. eucalyptus tree → 3. oak tree → lemur → fossa koala bear → dingo squirrel → cat Page 101: The Antarctic Answers will vary, for example: plankton → Antarctic cod → seal Page 102: In the savannah plains 2. Small insects. Answers will vary, for example: 3. Birds. grass → gazelle → hyena 4. There will be fewer of them as they are at the top of the food chain. Page 103: In the rainforest 5. Answers will vary, for example jaguars, leopards, tigers. banana → monkey 6 → whale → lion Answers will vary, for example: → tiger Cambridge Primary Ready to Go Lessons for Science Stage 6: Answers to photocopiable pages Page 104: In a pond Plugs Answers will vary, for example: 1. Metal. water lily → frog → heron 2. Plastic or rubber. Page 106: Food chains assessment 1. leaf → ant → thrush → owl 2. Leaf. 3. Primary consumer. 4. 2 3. Plastic or rubber. 4. They are insulators. Pages 118–19: Changing the brightness of lamps in a circuit 1&2 5. Ant / thrush. 1. Personal response. 6. Thrush for ant; owl for thrush. 2. Answers will vary; ensure that all components listed are included in the circuit drawn. 7. There may be more ants, so more leaves would get eaten. If the owls don’t have thrushes to eat they will need to find other prey – different birds or small creatures – otherwise their numbers will decrease. Unit 2B: 6.4 Electrical conductors and insulators Page 108: Making circuits Answers will vary; all circuits should require cells (batteries), lamps and wires at least. 3–4. Personal response. 5. Increasing the number of cells (batteries). 6. Personal response. Page 121: Changing the number of cells (batteries) a) right b) right c) right Page 109: Electrical conductors Page 122: Improving a circuit Personal response. Personal response. Page 111: Electrical insulators Page 124: Changing simple circuits 1 Results Personal response. 1. Conclusion Non-metals are good electrical insulators. Page 113: Good electrical conductors 2. Results Personal response. Conclusion Metals are good electrical conductors. Page 115: Electrical insulators around school 1. Answers will vary; see the photocopiable page for an example. 2. Non-metals, for example plastics and rubber. 3. a) dim b) brighter Page 125: Changing simple circuits 2 1. Page 116: Electrical insulators in the home Saucepan 1. Handle. 2. Plastic or wood. 7 Cambridge Primary Ready to Go Lessons for Science Stage 6: Answers to photocopiable pages 2. 3. The car would not move – or it might go backwards! Page 139: Circuit symbols 1. 3. higher or lower 4. no dimmer lamp Pages 127–28: Testing the thickness of wires in a circuit 1 & 2 buzzer 1–5. Personal response. 6. The thicker the wire the lower the resistance / the thinner the wire the greater the resistance. 7. thicker brighter or thinner dimmer Pages 130–31: Making a dimmer switch 1 & 2 1–2. Personal response. 3. a) The shortest. b) The distance around the circuit is shorter. Page 133: Circuit symbol cards Laminate these cards for use in the Main activities. Page 134: Circuit symbols Information sheet for the Main activities. Page 135: Drawing circuits Personal response; check for correct use of circuit symbols. Page 137: Using circuits 1. He could use more cells (batteries) or a bigger lamp. 2. a) The lamp will glow brighter. 3. The lamp might fuse. 4. Answers will vary, for example: mountain rescue, caving, looking in a dark cupboard. Page 138: How do circuits work? 1. She could add more cells (batteries). 2. battery (cell) wire 8 lamp Circuit symbol cell (battery) brighter switch (on) Equipment lamp M motor switch wires 2. If there is a gap then the circuit will not work. Unit 3A: 6.5 Caring for the environment Page 141: How do humans affect the environment? Answers will vary, for example: Positive effect 1. Refuse disposal 2. Recycling 3. Saving water and energy Negative effect 1. Building on the natural environment 2. Pollution 3. Oil spills Page 143: Environmental audit Personal response. Pages 145–46: Collecting environmental data 1 & 2 Personal response. Page 148: Using red cabbage indicator 1. Liquid red cabbage indicator rainwater lemon juice white vinegar acid rain (in jar) Colour Colour with red cabbage indicator purple clear yellow clear clear clear red pink orange Cambridge Primary Ready to Go Lessons for Science Stage 6: Answers to photocopiable pages 2. The chalk dissolved with some fizzing and the liquid turned purple. 3. Red. 4. a) Lemon juice b) White vinegar Page 149: What can acid rain do to buildings? 1. Personal response. 2. The buildings erode as the acid rain wears away / dissolves the soft rock. Pages 151–52: Collecting evidence of pollution in the air 1 & 2 Page 159: The ozone layer 1. Personal response: The learners need to design the Sun, oxygen molecules, ozone molecules and CFCs. 2. Personal response: The cartoon needs to show the Sun splitting oxygen molecules, and these atoms joining another oxygen molecule to make ozone. Then the CFCs come along and steel oxygen. Page 161: Deforestation 1. a) Areas of the forest are cleared and some animal habitats are destroyed. b) Huge expanses of forest and many more habitats are destroyed, and the ground and air can be polluted. Answers will vary; soot or dark deposits should be seen. c) Mining requires large areas of the forest to be cleared, and access for vehicles and large machinery also harm other areas of the forest. Page 154: Pollution 1. s o b r k y m p l i r u g r t o 2. That a particular animal has died out. k p e t r o l y e r a p t n o g c u t g l i b a 3. Answers will vary, for example woolly mammoth, dodo, North African elephant, Atlas bear, Javan tiger, koala lemur, Western black rhinoceros. i v h r e s p s i s e m u f l e n e p o o s y t Page 163: Reduce, reuse, recycle 1. Answers will vary, for example: Item Alternative pesticides organic pesticides 2. It affects people’s health. Page 155: Pollution in cities 1. Answers will vary, for example: exhaust emissions, industrial waste, litter. 2. Answers will vary, for example: council recycling initiatives; reducing traffic in town centres / introducing low-emission zones; encouraging use of bicycles with the introduction of cycle lanes; increasing taxes on petrol and flying to encourage people to use public transport and to take fewer flights; unleaded petrol is becoming more common; introducing bus and tram lanes to make public transport more attractive. cars walk or cycle electricity daylight, turning off lights and not leaving electrical items on stand-by water showers instead of baths 3. Personal response. Page 157: Global warming (the greenhouse effect) Reason stop poisoning soil save fuel and reduce pollution save fuel and reduce pollution avoid water shortages and reduce the fuel used for heating 3. 1. Earth 2. Sun 3. atmosphere 4. greenhouse gases 4. Answers will vary, for example paper, glass, aluminium cans. 5. pollution Page 164: Swap shop 6. fossil fuels Template to create an invitation to swap items with friends. 7. deforestation 9 Cambridge Primary Ready to Go Lessons for Science Stage 6: Answers to photocopiable pages Page 166: Being environmentally friendly 1. b) c) e) f) g) i) Page 178: The direction of forces 1. j) 2. Personal response. Unit 3B: 6.6 Mass and weight Pages 168–69: Measuring mass Personal response. Page 171: Measuring weight in newtons (N) Personal response. Page 172: Measuring weight in newtons (N) Personal response. 2. Twist. 3. Personal response. Page 180: Energy in movement Thing that moves What is moving? an American footballer a helicopter his body Where does it get its energy from? food propellers fuel a frog jumping legs food riding a bicycle wheels the cyclist Approximately 100g = 1 newton Page 174: Measuring in kilograms (kg) and newtons (N) Personal response. Page 175: Measuring in kilograms (kg) and newtons (N) Personal response. Approximately 100g = 1 newton Page 177: The direction of forces Page 181: Energy in movement Thing that moves What is moving? a fish swimming a runner an aeroplane Personal response. tail and body What is its source of energy? food / muscles arms and legs engine Personal response. food / muscles fuel Personal response. Page 183: Balanced and unbalanced forces Object Balanced or Forces Which unbalanced involved force is forces? strongest? a sinking unbalanced upthrust gravity ship (buoyancy) and gravity 10 a falling rock unbalanced mass and gravity gravity a parachute unbalanced air resistance and gravity gravity a table balanced mass and gravity they are equal Cambridge Primary Ready to Go Lessons for Science Stage 6: Answers to photocopiable pages Object Balanced or Forces Which unbalanced involved force is forces? strongest? a hot air balanced air they are balloon resistance equal floating and in the air gravity Page 185: Investigating friction Personal response. The smoothest surface is best for reducing friction as the smoother the surface the less friction there is. Conclusion bigger slower or smaller faster / quicker Air resistance is acting against the force of gravity. The bigger the canopy, the greater the air resistance, and so it takes longer to reach the ground. The smaller the canopy, the lower the air resistance, and so it takes less time to reach the ground. Page 192: Parachutes 1. Page 187: Air resistance 1. a) flat b) folded into four c) screwed up 2. The screwed-up paper fell fastest. air resistance 3–4. Personal response. gravity Pages 189–90: Making parachutes 1&2 Personal response. 2. Thin paper made the best canopy because it took longest to fall to the ground. 11