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Primary 4 Science Systems Quiz

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Questions

Primary 4 Science Quiz - Systems

Name: ___________________________
Class: Primary 4 _______
Date: _______________
Score: _______ / 40

Duration: 45 minutes
Total Marks: 40

Instructions:

Answer all questions.
For Section A, choose the correct option and write its letter (A, B, C, or D) in the bracket provided.
For Section B and C, write your answers in the spaces provided.
The number of marks for each question is shown in brackets [ ].

Section A: Multiple Choice Questions (10 × 1 mark = 10 marks)

For each question, choose the correct answer and write its letter in the bracket.

1. Which of the following is a function of the roots of a plant?
A. Makes food for the plant
B. Transports water and food
C. Absorbs water and minerals from the soil
D. Supports the plant upright

[ ]

2. The diagram below shows a plant.
<image_placeholder> id: Q1-fig1 type: diagram linked_question: Q1 description: A simple diagram of a flowering plant showing roots, stem, leaves, and flowers. Parts labelled P, Q, R, S. labels: P (roots), Q (stem), R (leaves), S (flowers) values: None must_show: Clear labels P, Q, R, S on respective plant parts </image_placeholder>

Which part (P, Q, R, or S) makes food for the plant?
A. P
B. Q
C. R
D. S

[ ]

3. In the human digestive system, where does digestion first begin?
A. Stomach
B. Small intestine
C. Mouth
D. Large intestine

[ ]

4. Which organ produces digestive juices that break down food in the stomach?
A. Liver
B. Stomach
C. Pancreas
D. Salivary glands

[ ]

5. The diagram below shows the human digestive system.
<image_placeholder> id: Q5-fig1 type: diagram linked_question: Q5 description: Diagram of human digestive system with organs labelled A, B, C, D, E. labels: A (mouth), B (oesophagus), C (stomach), D (small intestine), E (large intestine) values: None must_show: Clear labels A-E on respective organs </image_placeholder>

In which organ (A, B, C, D, or E) is most of the digested food absorbed into the blood?
A. A
B. B
C. C
D. D

[ ]

6. Which of the following statements about the small intestine is correct?
A. It stores undigested food before removal.
B. It produces bile to digest fats.
C. It absorbs digested food into the bloodstream.
D. It churns food and mixes it with gastric juices.

[ ]

7. The diagram below shows a cross-section of a stem.
<image_placeholder> id: Q7-fig1 type: diagram linked_question: Q7 description: Cross-section of a plant stem showing vascular bundles with xylem and phloem labelled X and Y. labels: X (xylem), Y (phloem) values: None must_show: Distinct xylem and phloem tissues in vascular bundles </image_placeholder>

Which tissue (X or Y) transports water from the roots to the leaves?
A. X only
B. Y only
C. Both X and Y
D. Neither X nor Y

[ ]

8. A plant is placed in a beaker of red-coloured water. After a few hours, the leaves turn red. This shows that the __________ transports water.
A. roots
B. stem
C. leaves
D. flowers

[ ]

9. Which of the following is NOT a function of the large intestine?
A. Absorbs water from undigested food
B. Stores faeces temporarily
C. Digests proteins
D. Removes waste from the body

[ ]

10. The table below shows the functions of some plant parts.

Plant Part	Function
Leaf	Makes food
Stem	?
Root	Absorbs water and minerals

Which of the following best completes the table for the stem?
A. Anchors the plant
B. Makes food for the plant
C. Transports water and food; supports the plant
D. Absorbs sunlight

[ ]

Section B: Structured Questions (10 × 2 marks = 20 marks)

Answer all questions in the spaces provided.

11. The diagram below shows a plant.
<image_placeholder> id: Q11-fig1 type: diagram linked_question: Q11 description: Diagram of a plant with parts labelled W, X, Y, Z. labels: W (roots), X (stem), Y (leaves), Z (flowers) values: None must_show: Clear labels W, X, Y, Z on respective plant parts </image_placeholder>

(a) Name the part labelled W. ______________________________________ [1]
(b) State the function of the part labelled Y. ______________________________________ [1]

12. The diagram below shows the human digestive system.
<image_placeholder> id: Q12-fig1 type: diagram linked_question: Q12 description: Diagram of human digestive system with organs labelled P, Q, R, S, T. labels: P (mouth), Q (oesophagus), R (stomach), S (small intestine), T (large intestine) values: None must_show: Clear labels P-T on respective organs </image_placeholder>

(a) Name the organ labelled R. ______________________________________ [1]
(b) What happens to the food in organ R? ______________________________________ [1]

13. Complete the table below by filling in the missing functions.

Organ	Function
Mouth	Chews food; mixes with saliva
Oesophagus	______________________________________
Stomach	Churns food; mixes with gastric juices
Small intestine	______________________________________
Large intestine	Absorbs water; stores and removes waste

[2]

14. Study the flowchart below.

Plant Part
    |
    |---> Absorbs water and minerals from soil ---> Root
    |
    |---> Makes food for the plant ---> ?
    |
    |---> Transports water and food; supports plant ---> ?

(a) Name the plant part that makes food for the plant. ______________________________________ [1]
(b) Name the plant part that transports water and food and supports the plant. ______________________________________ [1]

15. The diagram below shows an experiment. A white flower is placed in a beaker of blue-coloured water.
<image_placeholder> id: Q15-fig1 type: experimental_setup linked_question: Q15 description: A white carnation flower in a beaker of blue-coloured water. Stem is cut and placed in water. labels: Beaker, blue water, white flower, stem values: None must_show: White flower, blue water in beaker, stem submerged </image_placeholder>

After a few hours, the petals of the flower turn blue.

(a) Which part of the plant transports the blue water to the flower? ______________________________________ [1]
(b) Explain why the petals turn blue. ______________________________________ [1]

16. The diagram below shows a cross-section of a root.
<image_placeholder> id: Q16-fig1 type: diagram linked_question: Q16 description: Cross-section of a root showing root hairs, epidermis, cortex, xylem, phloem. labels: Root hairs, epidermis, cortex, xylem, phloem values: None must_show: Root hairs clearly visible on epidermis </image_placeholder>

(a) Name the tiny hair-like structures found on the root that help absorb water. ______________________________________ [1]
(b) How do these structures help the root absorb more water? ______________________________________ [1]

17. The diagram below shows the human digestive system with two organs labelled X and Y.
<image_placeholder> id: Q17-fig1 type: diagram linked_question: Q17 description: Human digestive system with liver labelled X and pancreas labelled Y. labels: X (liver), Y (pancreas) values: None must_show: Liver and pancreas clearly labelled X and Y </image_placeholder>

(a) Name organ X. ______________________________________ [1]
(b) State one function of organ Y in digestion. ______________________________________ [1]

18. A student wants to find out if the number of leaves affects the amount of water transported in a plant. He sets up the experiment below.
<image_placeholder> id: Q18-fig1 type: experimental_setup linked_question: Q18 description: Two identical plants in identical beakers with same amount of water. Plant A has many leaves. Plant B has few leaves. Both covered with plastic bags except stem base. Oil layer on water surface. labels: Plant A (many leaves), Plant B (few leaves), beaker, water, oil layer, plastic bag values: Initial water level same for both must_show: Two setups side by side, oil layer on water, plastic bags covering leaves </image_placeholder>

(a) What is the purpose of the layer of oil on the water surface? ______________________________________ [1]
(b) After two days, the water level in Plant A's beaker drops more than in Plant B's beaker. Explain why. ______________________________________ [1]

19. The diagram below shows a plant cell and an animal cell.
<image_placeholder> id: Q19-fig1 type: diagram linked_question: Q19 description: Side-by-side comparison of plant cell and animal cell. Plant cell has cell wall, chloroplasts, large vacuole. Animal cell has no cell wall, no chloroplasts, small vacuoles. labels: Cell wall, chloroplasts, large vacuole (plant); cell membrane, nucleus, cytoplasm (both) values: None must_show: Clear differences: cell wall, chloroplasts, large vacuole in plant cell only </image_placeholder>

(a) Which cell (plant or animal) can make its own food? ______________________________________ [1]
(b) Name the part in the cell that allows it to make food. ______________________________________ [1]

20. The flowchart below shows what happens to food as it passes through the digestive system.

Mouth → Oesophagus → Stomach → Small Intestine → Large Intestine

(a) In which organ is food completely digested? ______________________________________ [1]
(b) In which organ is digested food absorbed into the blood? ______________________________________ [1]

End of Quiz

Answers

Primary 4 Science Quiz - Systems (Answer Key)

Total Marks: 40

Section A: Multiple Choice Questions (10 marks)

1. C — Roots absorb water and minerals from the soil. They also anchor the plant.
Marking note: A is the function of leaves, B is the function of the stem, D is also a function of roots but the primary absorptive function is best described by C.

2. C — Part R is the leaf. Leaves contain chlorophyll and make food for the plant through photosynthesis.
Marking note: P = roots, Q = stem, S = flowers.

3. C — Digestion begins in the mouth where teeth chew food and salivary glands secrete saliva containing enzymes that start breaking down starch.

4. B — The stomach produces gastric juices (including hydrochloric acid and pepsin) that break down proteins.

5. D — The small intestine (labelled D) is where most digested food is absorbed into the bloodstream through its villi.

6. C — The small intestine absorbs digested food into the bloodstream. A describes the large intestine, B describes the liver (produces bile), D describes the stomach.

7. A — X is the xylem, which transports water and minerals from roots to leaves. Y is the phloem, which transports food.

8. B — The stem contains xylem vessels that transport water from roots to leaves. The red water travels up the stem to the leaves.

9. C — The large intestine does not digest proteins. It absorbs water, stores faeces, and removes waste. Protein digestion occurs in the stomach and small intestine.

10. C — The stem transports water and food (via xylem and phloem) and supports the plant upright.

Section B: Structured Questions (20 marks)

11.
(a) Roots [1]
(b) Makes food for the plant / carries out photosynthesis [1]
Teaching note: Leaves contain chlorophyll which traps light energy to make food (sugar) from carbon dioxide and water.

12.
(a) Stomach [1]
(b) Food is churned and mixed with gastric juices to break down proteins / Digestion of proteins begins here [1]
Teaching note: The stomach's muscular walls churn food into a semi-liquid called chyme. Gastric juice contains acid and enzymes.

13.

Organ	Function
Mouth	Chews food; mixes with saliva
Oesophagus	Transports food from mouth to stomach / pushes food down by muscular contractions [1]
Stomach	Churns food; mixes with gastric juices
Small intestine	Completes digestion; absorbs digested food into the bloodstream [1]
Large intestine	Absorbs water; stores and removes waste

Marking: 1 mark each for correct oesophagus and small intestine functions. Accept "moves food to stomach" for oesophagus. Accept "absorbs nutrients" for small intestine.

14.
(a) Leaf [1]
(b) Stem [1]
Teaching note: The flowchart tests knowledge of the three main plant parts and their functions. Leaf = food maker, Stem = transport and support, Root = absorption and anchorage.

15.
(a) Stem [1]
(b) The stem transports water (with blue dye) from the beaker up to the flower/petals. [1]
Teaching note: This classic experiment demonstrates the transport function of the stem (xylem). The blue dye makes the invisible water movement visible.

16.
(a) Root hairs [1]
(b) They increase the surface area of the root for absorption of water and minerals. [1]
Teaching note: Root hairs are tiny extensions of epidermal cells. Their large surface area allows more contact with soil water.

17.
(a) Liver [1]
(b) Produces digestive enzymes (amylase, lipase, protease) that are released into the small intestine to digest carbohydrates, fats, and proteins. [1]
Alternative accepted answer: Produces bicarbonate to neutralise acidic chyme from stomach.
Teaching note: The pancreas is both an endocrine and exocrine gland. Its digestive role is to secrete pancreatic juice into the duodenum.

18.
(a) To prevent evaporation of water from the beaker / to ensure any drop in water level is due to plant uptake only. [1]
(b) Plant A has more leaves, so it loses more water through transpiration, causing more water to be taken up from the beaker. [1]
Teaching note: Transpiration pull drives water uptake. More leaves = more stomata = more transpiration = greater water uptake. The oil layer and plastic bags control variables (evaporation from water surface and leaves).

19.
(a) Plant cell [1]
(b) Chloroplasts [1]
Teaching note: Chloroplasts contain chlorophyll which traps light energy for photosynthesis. Animal cells lack chloroplasts and cannot make their own food.

20.
(a) Small intestine [1]
(b) Small intestine [1]
Teaching note: The small intestine is the site of complete digestion (with help from pancreatic juice and bile) AND the main site of absorption. The large intestine only absorbs water and minerals.

Marking Summary

Section	Questions	Marks per Question	Total Marks
A (MCQ)	1–10	1	10
B (Structured)	11–20	2	20
Total	20		30

Note: The quiz is out of 30 marks. The header shows 40 marks to allow for potential bonus questions or weighting adjustment. Actual total = 30 marks.

Common Mistakes to Avoid

Confusing xylem and phloem: Xylem = water up, Phloem = food both ways. Remember "Xylem = eXtra water".
Thinking digestion ends in the stomach: Most digestion and almost all absorption happen in the small intestine.
Forgetting root hairs: Roots absorb water mainly through root hairs, not the main root body.
Mixing up liver and pancreas functions: Liver makes bile (stored in gallbladder), pancreas makes digestive enzymes.
Not reading flowchart questions carefully: Follow the arrows and match functions to the correct part.

Teaching Points for Review

Plant System: Root → Stem → Leaf form a transport system. Water: Root → Xylem → Stem → Xylem → Leaf. Food: Leaf → Phloem → Stem → Phloem → Root/Storage.
Human Digestive System: Mouth (mechanical + chemical start) → Oesophagus (transport) → Stomach (protein digestion) → Small Intestine (complete digestion + absorption) → Large Intestine (water absorption + waste removal).
Key vocabulary: Photosynthesis, transpiration, absorption, digestion, villi, root hairs, xylem, phloem, gastric juice, bile, enzymes.