Year 8 EOY Revision 1. People who have emphysema have damaged air sacs in their lungs. The diagrams show a section through a normal air sac and a section through a damaged air sac. (a) gas gas in out gas gas in out normal air sac damaged air sac Gas exchange takes place at the inside surface of the air sac when a person breathes. (i) Which two gases are exchanged at this surface of the air sac? ................................................ and ................................................... 1 mark (ii) The amount of gas exchanged is smaller in a damaged air sac. Explain why. ............................................................................................................. ............................................................................................................. 1 mark (b) The list shows four substances present in cigarette smoke. carbon particles carbon monoxide nicotine tar Choose from the list the substance which: (i) causes addiction to smoking cigarettes; ............................................................................................................ 1 mark 2.Linda had a piece of red sandstone. She hammered it into pieces and then ground them into a powder using a pestle and mortar. She put the powder into a measuring cylinder with water and shook the mixture. The contents settled. (a) Linda said her results showed that sandstone is a mixture of two substances. How could she tell, from the results, that sandstone is a mixture of substances? ..................................................................................................................... ..................................................................................................................... 1 mark (b) Linda then poured the cloudy water from the measuring cylinder through filter paper in a filter funnel. She said there might be salts dissolved in the colourless, clear liquid that came through the filter. (i) What could Linda do to find out if there were salts dissolved in the colourless, clear liquid? ............................................................................................................. ............................................................................................................. 1 mark (ii) What would she see if there had been salts dissolved in the colourless, clear liquid? ............................................................................................................. ............................................................................................................. 1 mark (c) Sandstone is a sedimentary rock. Four stages in the formation of sedimentary rock are listed below. They are not in the correct order. compacted deposited weathered transported Put these stages in the correct order. One has been done for you. stage 1 ................weathered................... stage 2 ..................................................... stage 3 ..................................................... stage 4 ..................................................... 1 mark 3. (a) Jacquie has a mobile phone. Energy is stored in the battery of the phone. The drawing shows the battery being charged. (i) Which energy transfer takes place in the battery as it is being charged? Tick the correct box. chemical to sound sound to thermal electrical to chemical thermal to electrical 1 mark (ii) When the battery is fully charged, Jacquie unplugs the phone. Which energy transfers take place when the mobile phone rings? Tick the correct box. chemical to electrical to sound electrical to chemical to sound kinetic to electrical to sound thermal to electrical to sound (b) Jacquie can change the ring-tone of her phone. The diagrams below show the patterns made by four sound waves on an oscilloscope screen. They are all drawn to the same scale. Write the letter of the sound wave that matches each of the descriptions below. (i) a loud sound with a low pitch ................. (ii) a quiet sound with a high pitch ................. (iii) a loud sound with a high pitch ................. 3 marks 4. The graph represents how antibiotics affect the number of bacteria in the body. number of harmful bacteria in the body 0 0 1 2 3 4 5 6 7 8 9 10 time, in days sandwich antibiotics eaten started (a) Use the graph to explain why the girls did not become ill until the day after eating the sandwiches. ..................................................................................................................... ..................................................................................................................... 1 mark (b) After taking the antibiotics for eight days Jenny was completely better. Explain why she got better. ..................................................................................................................... ..................................................................................................................... 1 mark (c) Leah should have taken the antibiotics for eight days. She felt much better after five days and stopped taking the antibiotics. Two days later she felt very ill again. Use the graph to help you explain why Leah became ill again. ..................................................................................................................... ..................................................................................................................... ..................................................................................................................... ..................................................................................................................... 2 marks (d) Food will keep longer if it is placed in a refrigerator at 2°C. Refrigeration does not kill bacteria. What effect does the low temperature have on bacteria? ..................................................................................................................... ..................................................................................................................... 1 mark Maximum 5 marks 5. Peter burns a piece of crispbread to find out how much energy is stored in it. Energy from the burning crispbread raises the temperature of the water in the test-tube. (a) Describe one way Peter has arranged the apparatus so that he is working safely. .......................................................................................................................... .......................................................................................................................... 2 marks (b) Peter wants to find out if potato crisps contain as much energy as crispbread. He does the experiment again using a piece of potato crisp. Suggest two things he must do to make the experiment a fair test. 1. ................................................................................................................. 2. ................................................................................................................. 1 mark The table shows some of the nutritional information from a packet of crispbread and a packet of potato crisps. 100 g of crisp bread 100 g of potato crisps (c) energy in kJ protein in g carbohydrate in g fat in g fibre in g 1455 11.6 58.1 7.3 14.7 2072 5.8 57.9 28.7 4.3 Peter burns 1.0 g of potato crisp instead of 1.0 g of crispbread in a similar experiment. What result will he get when he burns the potato crisp? Tick the correct box. The change in the temperature of the water will be greater. The change in the temperature of the water will be the same. The change in the temperature of the water will be smaller. There will be no change in the temperature of the water. 1 mark (d) (i) Fibre contains energy. Explain why this energy can not be used by the human body. ................................................................................................................. ................................................................................................................. 1 mark (ii) Use the table in part (b) to give two reasons for choosing crispbread rather than potato crisps as part of a balanced diet. 1. ............................................................................................................. ................................................................................................................. 2. ............................................................................................................. ................................................................................................................. 2 marks (e) Crispbread does not contain vitamin C. Which of the foods in the list below is the best source of vitamin C? Tick the correct box. cheese eggs fish oranges 1 mark 6. The drawing shows a water lily and some waterweed growing in a pond. flower water lily floating leaf surface of pond stalk X waterweed Y roots (a) Waterweed grows well at Y but not at X. Why is this? Tick the correct box. There is not enough food at X. There is not enough light at X. There is not enough oxygen at X. There is not enough water at X. 1 mark (b) Which named part of the water lily produces seeds? ..................................................................................................................... 1 mark (c) The drawing shows part of a food web in a pond. Use the information in the drawing to answer the questions. (i) Write three names from the food web to make a food chain which ends with pike. .............................. .............................. .............................. pike 1 mark (ii) Write the name of one predator in the food web and the name of one of its prey. Predator: .............................................................................................. Prey: .............................................................................................. 2 marks (d) Fish have gills and fins. How do these help the fish to live in water? Gills are for ................................................................................................... ...................................................................................................................... Fins are for ................................................................................................... ...................................................................................................................... 7. (a) Debbie put a paper cup into a glass beaker. She glued a magnet in the bottom of the paper cup. She glued another magnet in the bottom of the beaker. The magnets repelled. 2 marks paper cup N magnet S S magnet glass beaker N diagram A (not to scale) What two forces act on the paper cup and its contents to keep it in this position? 1. ........................................................... 1 mark 2. ........................................................... 1 mark (b) Debbie put 5 g of aluminum rivets into the paper cup. It moved down a little as shown in diagram B. N aluminium rivets S S N diagram B (not to scale) (c) Debbie removed the 5 g of aluminium rivets and put 5 g of iron nails into the cup. N S iron nails S N diagram C (not to scale) The paper cup moved down more with 5 g of iron nails than with 5 g of aluminium rivets as shown in diagram C. Give the reason for this. ..................................................................................................................... ..................................................................................................................... 1 mark
