Primary 4 Science Semestral Assessment 2 (End of Year) Paper 1

TuitionGoWhere Practice Paper - Science Primary 4

SA2 Answer Key — Version 1 of 5

Paper: SA2 (End-of-Year Examination) Total Marks: 50

Section A: Multiple Choice Questions (10 marks)

1. C) Grass

• Marking note: Grass is a living plant. Rock, plastic bottle, and metal spoon are non-living. (1 mark)

2. B) They can grow.

• Marking note: All living things grow. Not all living things can fly, are green, or live on land. (1 mark)

3. C) Cloud

• Marking note: A cloud is made of water droplets and is non-living. Butterfly, mushroom, and fish are living things. (1 mark)

4. B) It can grow and reproduce.

• Marking note: Growth and reproduction are key characteristics of living things. A plastic flower cannot grow or reproduce. (1 mark)

5. B) Dog, cat, fish

• Marking note: All three are living things. The other options contain at least one non-living item. (1 mark)

6. B) They can move from place to place.

• Marking note: Not all living things can move from place to place (e.g., plants are living but do not move from place to place). This is NOT a universal characteristic of living things. (1 mark)

7. B) grow.

• Marking note: A seed germinating and developing into a plant is an example of growth, a characteristic of living things. (1 mark)

8. B) A sunflower turning towards sunlight.

• Marking note: This is a living thing responding to a stimulus (light). The other options involve non-living things or physical changes. (1 mark)

9. B) Sunlight, water, air, and food

• Marking note: Living things need sunlight, water, air, and food to survive. (1 mark)

10. C) Living things need food, water, and air to survive.

• Marking note: This is the only correct statement. Not all living things can move on their own (e.g., plants), non-living things cannot grow and reproduce, and non-living things do not respond to stimuli. (1 mark)

Section B: Short Answer Questions (20 marks)

11. (4 marks — 1 mark each)

• Marking note: Cats and potted plants are living things. Wooden chairs and water are non-living things. Accept only L or N.

12. (2 marks — 1 mark each)

Accept any two of the following:

• They can grow.

• They can reproduce (produce young/offspring).

• They need food and water (or nutrients).

• They respond to changes around them (stimuli).

• They can breathe / respire (take in air/gases).

• They can excrete (remove waste).

• Marking note: Award 1 mark for each correct characteristic, up to 2 marks. Answers must describe characteristics shared by ALL living things.

13. (2 marks)

A car is a non-living thing because:

• It cannot grow on its own. (1 mark)
• It cannot reproduce / it does not need food and water to survive (it uses fuel, not food in the biological sense). (1 mark)

Alternative acceptable answers:

• It cannot respond to stimuli.

• It cannot excrete waste.

• It does not breathe/respire.

• Marking note: Award 1 mark for each valid reason, up to 2 marks. The key point is that movement alone does not make something a living thing; the car lacks other essential life processes.

14. (4 marks — 1 mark each)

Accept any one valid observable characteristic for each organism:

• Marking note: Award 1 mark per correct characteristic. The characteristic must be observable and must be a characteristic of living things.

15. (3 marks)

Disagree with the student. (1 mark)

A mushroom is a living thing because: (2 marks)

• It can grow (it increases in size over time). (1 mark)
• It can reproduce (it produces spores to make new mushrooms). (1 mark)

Alternative acceptable reasons:

• It needs food and water to survive.

• It responds to changes in its environment.

• Marking note: Award 1 mark for stating disagreement. Award up to 2 marks for valid reasons. The key misconception to address is that movement is NOT a requirement for being a living thing. Fungi (mushrooms) are living organisms.

Section C: Structured / Application Questions (20 marks)

16. (4 marks)

(a) Three living things in a pond ecosystem: (3 marks — 1 mark each)

• Fish
• Water lily (plant)
• Frog

Alternative acceptable answers: Any living organism found in a pond (e.g., duck, algae, dragonfly, turtle).

(b) One non-living thing: (1 mark)

• Water / Rock / Sunlight / Mud / Sand

• Marking note: Award 1 mark per correct answer. Answers must be appropriate for a pond ecosystem.

17. (4 marks)

(a) The object is a non-living thing. (1 mark)

(b) Two reasons: (3 marks — 1.5 marks each, or 1 mark + 2 marks)

(i) It does not grow — living things grow and develop over time. (1–1.5 marks)

(ii) It does not reproduce — living things can produce offspring of their own kind. (1–1.5 marks)

Alternative acceptable reasons:

• It does not need food or water.

• It does not respond to touch (stimulus).

• Marking note: Award 1 mark for correct classification in part (a). Award up to 3 marks for valid reasons in part (b). Reasons must reference specific observations from the question.

18. (4 marks)

(a) The main difference: (2 marks)

• Organism X (butterfly) goes through four stages including a pupal/chrysalis stage, while Organism Y (grasshopper) goes through only three stages and has no pupal stage. (2 marks)

Alternative acceptable answer:

• Organism X undergoes complete metamorphosis (egg → larva → pupa → adult), while Organism Y undergoes incomplete metamorphosis (egg → nymph → adult). (2 marks)

(b) The nymph stage most closely resembles the adult grasshopper. (1 mark)

• This is because the nymph looks similar to the adult but is smaller and does not have wings yet. (1 mark)

• Marking note: For part (a), award 2 marks for a clear comparison. For part (b), award 1 mark for identifying the nymph and 1 mark for the explanation.

19. (4 marks)

(a) Living things: Item 1 (Ant), Item 3 (Mushroom), Item 5 (Grasshopper) (2 marks)

• Marking note: Award 2 marks if all three are correct. Award 1 mark if one or two are correct.

(b) Non-living things: Item 2 (Fallen leaf), Item 4 (Puddle of water), Item 6 (Plastic wrapper) (2 marks)

• Marking note: Award 2 marks if all three are correct. Award 1 mark if one or two are correct. Note: A fallen leaf is non-living because it has been separated from the tree and can no longer carry out life processes.

20. (4 marks)

(a) Student B is correct. (1 mark)

(b) Explanation using two characteristics of living things: (3 marks)

Fire is a non-living thing because:

• Fire cannot reproduce — it cannot produce young or offspring of its own kind. (1.5 marks)
• Fire cannot respond to changes like living things do — it does not react to stimuli in a biological way; it simply reacts to physical/chemical conditions (fuel, oxygen). (1.5 marks)

Alternative acceptable reasons:

• Fire does not excrete waste.

• Fire does not grow in the biological sense (it spreads, but this is not the same as growth in living things).

• Fire does not need food in the biological sense.

• Marking note: Award 1 mark for identifying Student B. Award up to 3 marks for explanation. The key teaching point is that fire exhibits some properties that resemble living things (it "grows," "moves," and "needs air"), but it lacks essential life processes such as reproduction and response to stimuli.

END OF ANSWER KEY

Total: 50 marks

Summary of Marks by Section