Question 1

The following are characteristics of organism X.
A  It has wings.
B  It has three body parts.
C  It has three pairs of legs.
D  It reproduces by laying eggs.
Which characteristics can be used to conclude that organism X is an insect?

Accepted Answer

C. B and C only. An insect is defined as an animal with three body parts (head, thorax, abdomen) and three pairs of legs. Wings and laying eggs are not unique to insects (birds also have wings and lay eggs).

Question 2

Q, R, S and T represent the different stages in the life cycle of a butterfly. The butterfly is able to reproduce at stage R. At which stage, Q, R, S and T, is the butterfly considered a pest to farmers?

Accepted Answer

D. T. R is the adult (since it can reproduce). Going backwards: Q is pupa, T is larva (caterpillar), S is egg. The caterpillar (larva) eats leaves voraciously, so T is the pest stage to farmers.

Question 3

Scientists observed that Island P had no plants or animals. A few years later, they found new plants growing there. The diagram shows Island P and a nearby island Y. They also observed that some fruits that were found on Island Y were also present on Island P. Which of the fruits A, B, C, and/or D are most likely to be found on both islands? [Table: Fruit A with waterproof layer; Fruit B with wings; Fruit C light with tiny hairs; Fruit D hard pod]

Accepted Answer

C. A, B and C only. Since water and wind both flow from Island Y toward Island P, seeds dispersed by water (A — waterproof layer) and by wind (B — wings; C — light with tiny hairs) can be carried to P. D (hard pod) is dispersed by explosive/self-mechanism and cannot cross water or wind.

Question 4

Process X takes place in the human female reproductive system. In which part of the flower Z does a similar process occur?

Accepted Answer

D. D. Process X is fertilisation — the joining of male and female sex cells. In flowers, fertilisation takes place in the ovary (part D), where the pollen nucleus fuses with the egg cell in the ovule.

Question 5

The table shows the main functions of organs W, X, Y and Z that are part of the human digestive system. What are organs W, X, Y and Z?

Accepted Answer

C. W:Small intestine, X:Stomach, Y:Large intestine, Z:Mouth. W absorbs digested food → small intestine (which also digests). Y absorbs water → large intestine. The other digestive organs are mouth and stomach, so X = stomach, Z = mouth.

Question 6

Three of the leaves from the pot of plant were wrapped with three different types of plastic bags of the same size as shown in the table. The pot of plant was left under bright sunlight for some time. Which of the following graphs correctly represents the amount of food made by leaves, A, B and C, after five hours? [Graphs: (1) A medium, B tallest, C shortest; (2) A shortest, B medium, C tallest; (3) A medium, B tallest, C zero; (4) A medium, B medium, C zero]

Accepted Answer

C. Graph 3. Leaf C (black bag) gets no light → no photosynthesis → no food. Leaf B (clear bag with holes) gets light + CO₂ exchange → most food. Leaf A (clear sealed bag) gets light but limited CO₂ → less food than B. So B tallest, A medium, C none.

Question 7

The diagram shows the different paths taken by food and water in a plant with parts A, B, C and D. Which of the following represents A, B, C and D?

Accepted Answer

A. A:leaf, B:stem, C:root, D:fruit. Food (made in leaf) travels from leaf → stem → root/fruit; water (absorbed by root) travels root → stem → leaf/fruit. A makes food and receives water = leaf; C absorbs water and receives food = root; B is the transport pathway = stem; D only receives water = fruit.

Question 8

A group of students carried out an investigation to test their hypothesis. They did the following: Rest for 2 minutes and record initial breathing rate. Perform different exercises (walk, jump and run) for 1 minute each. Count their breathing rate for 30 seconds immediately after each exercise. Record all data in a table. Create a bar graph to compare results. Which hypothesis is most suitable for this investigation?

Accepted Answer

A. The higher the exercise intensity, the higher the breathing rate.. The variable being changed is the type/intensity of exercise (walk → jump → run = increasing intensity), and the variable measured is breathing rate. So the hypothesis must relate exercise intensity to breathing rate.

Question 9

Study the flowchart. [Flowchart: Cells → Does it have a nucleus? Yes → Does it have chloroplasts? Yes → P; No → Does it have a cell wall? Yes → Q; No → R] Where are cells, P, Q and R, taken from?

Accepted Answer

A. P:Leaf of plant, Q:Root of plant, R:Skin of human. P has nucleus + chloroplasts → green plant cells (leaf). Q has nucleus + cell wall but no chloroplasts → non-green plant cell (root). R has nucleus, no chloroplasts, no cell wall → animal cell (human skin).

Question 10

Study the food web. [Food web: F→E, F→A (via C arrow inward), C→A, C→E, C→B (downward via D), D→E, D→B, B→A] Which one of the following shows the correct relationship among the various organisms in the food web?

Accepted Answer

C. Prey only: D and F; Predator only: A and E; Both prey and predator: B. C is the producer (eaten by F and D — only has arrows out). F is only eaten (by E) so prey only. A and E are top predators (only have arrows in, never eaten). B is both eaten (by A) and eats others (D). So D and F = prey only; A and E = predator only; B = both.

Question 11

The graph shows the change in the area covered by plant G in a garden. Animal X was introduced to the garden community at week 4. [Graph: Area covered by plant G is flat from weeks 1–4 then rises steeply from week 4 to week 6] Which of the statements could explain the increase in the area covered by plant G after week 4?
A  Animal X helped plant G disperse its seeds.
B  Animal X preyed on animals that fed on plant G.
C  Animal X fed on plant G and plant G reproduced.
D  The waste from animal X helped plant G grow faster.

Accepted Answer

C. A, B and D only. A (seed dispersal), B (removing predators of G), and D (waste as fertiliser) all increase plant G coverage. C is incorrect because if Animal X feeds on plant G, the plant population would decrease, not increase, regardless of reproduction.

Question 12

Three organisms, R, S and T, have characteristics that help them survive in their habitat as shown in the table. Which of the following organisms' characteristics have been correctly matched to their function?

Accepted Answer

B. To breathe in water: T; To reduce water loss: R; To float on water: S. Needle-shaped leaves (R) reduce surface area → reduce water loss. Air spaces in leaf stalk (S) allow oxygen storage and gas exchange — to breathe in water. Trap air bubbles (T) provides buoyancy — to float on water.

Question 13

The PSI (Pollutant Standards Index) gives an indication of air quality. The table shows what the air quality is like based on the PSI value. The PSI values of a town over five days are shown in the table. [Table: Day 1 — 46; Day 2 — 48; Day 3 — 123; Day 4 — 147; Day 5 — 144] Which one of the following is most likely to have caused the PSI value to increase from Day 2 to Day 4?

Accepted Answer

B. More forest fires happened nearby.. Forest fires release large amounts of smoke/particles that significantly raise the PSI. Cutting a few trees wouldn't sharply spike PSI, growing vegetables doesn't pollute, and switching to electric cars would lower PSI.

Question 14

Plants use their leaves to make food through the process of photosynthesis. Which of the following best represents the letters A, B, C, D and E during photosynthesis?

Accepted Answer

D. A:Sunlight, B:Oxygen, C:Carbon Dioxide, D:Water, E:Glucose. During photosynthesis: A (from the sun) = sunlight, B (released as a product) = oxygen, C (absorbed from air) = carbon dioxide, D (absorbed from stem/roots) = water, E (food made, transported down stem) = glucose.

Question 15

Mr Chan used two set-ups, A and B, to conduct an investigation. When he poured water into set-up A, only a small amount of water flowed into the flask as shown. However, when he poured the same amount of water into set-up B, all the water flowed in. Which of the following best explains Mr Chan's observation?

Accepted Answer

C. The glass tube in set-up B allowed air to escape.. In set-up A, air inside the flask had no way to escape, so it blocked water from entering. In set-up B, the extra glass tube let air escape as water poured in, so all the water could flow into the flask.

Question 16

The diagram shows the water cycle. Which of the following correctly identifies X, Y and Z?

Accepted Answer

D. X:evaporation, Y:condensation, Z:cloud. X: water → water vapour = evaporation. Y: water vapour → cloud (Z) = condensation. Z = cloud (since it then falls as rain). Therefore X=evaporation, Y=condensation, Z=cloud.

Question 17

Four identical containers, P, Q, R and S, were filled with the same amount of water. They were placed at four different locations under varying conditions for a day as shown. The conditions remained constant throughout the experiment. Which of the following graphs shows the possible amount of water left in containers P, Q, R and S after one day?

Accepted Answer

A. P medium, Q taller, R shortest, S tallest. Highest evaporation = sunny + windy (R) → least water. No sun, no wind (S) → most water. Sunny only (Q) and windy only (P) are in between, with Q (sunny) losing slightly more than P (windy). So order from most to least water: S > Q > P > R, matching graph (1).

Question 18

The diagram shows four circuits with identical batteries and bulbs. Which of the bulbs, A, B, C or D, will be the least bright?

Accepted Answer

A. A. In series (circuit A), the same voltage is split among three bulbs, so each bulb receives the smallest share. In parallel circuits (B, C, D), each bulb gets the full battery voltage and shines at full brightness. So bulbs in A are least bright.

Question 19

The diagram shows a toy with an electric circuit. The table shows the observations when the two switches in the circuit are open and/or closed. Which of the following represents the circuit in the toy? [Diagrams of four circuit options]

Accepted Answer

A. Option 1. Each switch must independently control its own component, so the light and buzzer must each be in their own parallel branch, with one switch per branch. Option 1 places S1 in series with the light branch and S2 in series with the buzzer branch — closing either switch lights its own component independently.

Question 20

The diagram shows three magnets with ends, CD, EF and GH. Which ends will repel?

Accepted Answer

D. D and H. Since the magnets are aligned without flying apart, the adjacent pairs D–E and F–G must attract (opposite poles). If D and E are opposite, the ends shown to be inferred follow: assuming D=N, then E=S, F=N, G=S, and H=N (and C=S). The ends C(S) and H(N) — would attract; D(N) and H(N) — repel.

Question 21

Ali strokes a nail 50 times with a magnet as shown. He brought the nail near a pile of iron pins and observed that it did not attract any of the iron pins. Which of the following explains his observation?

Accepted Answer

C. The nail is made of non-magnetic material.. Only magnetic materials (iron, steel, nickel, cobalt) can be magnetised by stroking. If the nail attracts no iron pins after 50 strokes, the nail must be made of a non-magnetic material.

Question 22

Marble R was rolling from point X on a carpeted floor. It was hit by marble S causing a change. Marble R continued moving and eventually stopped at point Y as shown. Based on the experiment, what can be concluded about the effects of forces acting on marble R?
A  A force can stop a moving object.
B  A force can change the size of an object.
C  A force can change the direction of a moving object.

Accepted Answer

B. A and C only. Marble R was stopped by friction (A — force can stop a moving object) and its direction changed when hit by S (C — force can change direction). The marble's size did not change, so B is not supported.

Question 23

Belle hung two identical objects, A and B, on two identical springs. Object A was hung in the air while object B was hung in a container of sand as shown. She then lifted the two springs with the object upwards by 5cm. Which one of the following statements is incorrect?

Accepted Answer

C. More gravitational force is acting on object A than on object B.. Objects A and B are identical and have the same mass, so the same gravitational force acts on both. Statement C is therefore incorrect. The other statements correctly describe extra downward friction from sand on B (D), the need for more lifting force (A), and that gravity acts on both (B).

Question 24

Sea turtle hatchlings, the young of turtles, crawl to the sea after hatching. They are guided by light reflected off the water as they make their way to the sea. However, bright lights from nearby carparks can confuse them. [Diagrams A, B, C, D: streetlamps with different shielding/directions over the carpark next to the sea] Which streetlamp, A, B, C or D, is least likely to confuse hatchlings?

Accepted Answer

B. B. A streetlamp that is shielded/directed downwards onto the carpark only (not spilling light toward the beach or sky) minimises the stray light reaching the hatchlings. Option B shows a fully downward-shielded lamp, so it is least likely to confuse them.

Question 25

Dave attached three identical pieces of wax, A, B and C, to a metal frame with equal sides as shown. When Dave heated the frame at a particular spot, the wax melted in the following order, B, A, C. At which spot, W, X, Y or Z, did Dave heat the metal frame?

Accepted Answer

A. W. Wax closest to the heat source melts first. Order B → A → C means B is closest, A second, C furthest. Spot W (the left side) is closest to B, slightly further from A, and furthest from C, matching the observed melting order.

Question 26

Maverick set up an experiment as shown to compare how well four rods, A, B, C and D, made of different materials, conduct heat. The similar-sized rods at 30°C were placed in a container of crushed ice at the same time. [Table of temperatures after 5 minutes: A — 20°C; B — 14°C; C — 8°C; D — 25°C] What can Maverick conclude about the heat conductivity of the materials of the rods, A, B, C and D?

Accepted Answer

C. B is a better conductor of heat than A.. The rod losing the most heat (lowest final temperature) is the best conductor. C (8°C) lost the most heat → best conductor; D (25°C) lost the least → poorest conductor. B (14°C) lost more heat than A (20°C), so B is a better conductor than A.

Question 27

The diagram shows a metal spoon in a bowl of ice cream. Which graph shows the changes in temperature of the metal spoon and the ice cream over time? [Key: solid line = Ice cream, dashed line = Metal spoon]

Accepted Answer

B. Ice cream rises, spoon falls, meeting at same temperature. The metal spoon (warmer, at room temperature) loses heat to the colder ice cream. So the spoon's temperature falls (dashed line falls) and the ice cream's temperature rises (solid line rises) until they meet at the same temperature (thermal equilibrium).

Question 28

Jace carried out an experiment with a pendulum. He lifted the bob to position A and let it swing to position B, C and then back to X. Which graph shows how the gravitational potential energy of the bob changes as it swings from position A to C and to X?

Accepted Answer

D. Graph 4. GPE is highest at A and X (highest points) and lowest at C (lowest point). The graph must show high GPE at A, falling to a minimum at C, then rising back to high at X — with the intermediate B points at medium height. Graph 4 shows this U-shape with maxima at A and X and minimum at C.

P6 Science SA2 2025 — Anglo Chinese

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