Jeddah Knowledge International School Biology Revision Pack Answer key 2016-2017 Quarter 3 Grade 9 Name: Section: ANSWER KEY- SCIENCE GRADE 9, QUARTER 3 1
Mark Scheme Multiple Choice Part A 1. Which gas is needed for photosynthesis? B) Carbon dioxide 2. What type of energy is needed for photosynthesis to happen? A) Light 3. What is produced as a waste by-product from photosynthesis? A) Oxygen 4.The green substance needed to absorb energy for photosynthesis is: C) Chlorophyll 5.Tomatoes in a greenhouse grow faster if the carbon dioxide concentration is increased. This shows that: B) Carbon dioxide concentration must have been a limiting factor. 6. Why do plants need nitrate ions? C) To make amino acids that are then used to make proteins. 7. A plant with yellow leaves could be growing in soil deficient in: A) Magnesium ions. ANSWER KEY- SCIENCE GRADE 9, QUARTER 3 2
Mark Scheme Multiple Choice Part B 1. Which of the following is NOT a characteristic shared by all plants? a) Seeds 2. Water loss in a leaf is prevented by the d) Cuticle. 3. Photosynthesis uses sunlight to make food from water and a) Carbon dioxide. 4. What could happen if a plant s phloem does not work correctly? b) The plant might be short of food. 5. Which of the following takes water and minerals from the roots to the shoot? d) Xylem 6. One function of a stem is to c) Transport food. 7. What cell part captures energy from the sun to make food? b) Chloroplasts 8. What does xylem do? a) Carries water and minerals ANSWER KEY- SCIENCE GRADE 9, QUARTER 3 3
9. Gas exchange through the stems or leaves of a plant takes place through the b) Stomata 10. Photosynthesis is important because b) Photosynthetic organisms form the base of most food chains 11. The energy that starts the process of photosynthesis comes from a) Sunlight. 12. Stomata are important because they a) Play a role in gas exchange. 13. By which process do plants make their own food from carbon dioxide and water? c) photosynthesis 14. Why are many plants green? a) Chlorophyll reflects green light 15. What gas do plants take in to make food? a) Carbon Dioxide 16. What is the pigment colour in chlorophyll? d) Green Part C Applying Knowledge 17. Plants absorb mineral ions from the soil through their ROOTS The mineral ions are then transported up the stem through XYLEM vessels. 18.i) A root hair cells B palisade cells C stomata cells D xylem cells ANSWER KEY- SCIENCE GRADE 9, QUARTER 3 4
Q19) i) A description including two of the following points chloroplasts contain chlorophyll (1) which absorb (sun)light (1) for photosynthesis (1) to produce glucose/sugar (1) Q20) (i) Name the vessel that transports water and mineral ions through the plant. Xylem (1) (ii) Energy is needed to transport sugars through the plant. Which cell component supplies energy that can be used for the transport of sugars through the plant? Put a cross ( A cell wall B chloroplast C nucleus D vacuole ) in the box next to your answer. (1) 21 C. photosynthesis 22 A. chlorophyll 23 D. cellular respiration 24 E. stoma 25 B. transpiration 26 A. photosynthesis 27 C. transpiration 28 G. chlorophyll 29 D. cellular respiration 30 B. stoma ANSWER KEY- SCIENCE GRADE 9, QUARTER 3 5
31 H. glucose 32 A 33 B 34 D 35 E 36 A- cuticle 37 C 38 C Palisade cells 39 Sample answer: The waxy cuticle protects a plant from water loss, but the leaf also has small openings called stomata. When they are open, carbon dioxide can enter the leaf, or oxygen or water vapor can exit. 40 Sample answer: All life on earth needs oxygen to survive. Photosynthesis provides that oxygen. Something in the pond must be interfering with the process of photosynthesis and the production of oxygen. Also, if the plants are dying, there is no food for the animals and insects. A possible cause might be chemicals introduced into the pond or a change in environmental conditions. 41- Possible answer: Plants, animals, and even people are all connected in the food chain. When there is no place for native plants and animals to live, that balance can be interrupted. We see this happen when a certain animal population, such as mice, gets out of control or when a plant such as purple loosestrife takes over a marsh. We need a nature preserve to help maintain balance in at least part of our county. ANSWER KEY- SCIENCE GRADE 9, QUARTER 3 6