Question 1

Which one of the following is not a characteristic of all living things?

Accepted Answer

They give birth to young alive.. Not all living things give birth to live young; many lay eggs or reproduce through other means. The other options (growing, responding to changes, needing air/food/water) are fundamental characteristics of all living things.

Question 2

Study the diagrams below.
Which of the following statements is correct?

Accepted Answer

Both A and B need air, food and water to survive.. Diagram A shows a horse (an animal) and Diagram B shows a palm tree (a plant). Both animals and plants are living things, and all living things need air, food, and water to survive. Animals cannot make their own food, while plants can. Both can grow and reproduce.

Question 3

Study the classification table below.
Based on the classification table above, which of the headings below are correct?

Accepted Answer

Heading Y: Can reproduce; Heading Z: Can respond to changes. Heading Y shows a cat with kittens, illustrating reproduction. Heading Z shows a person reacting to a loud noise, illustrating response to changes. Thus, option (1) correctly matches the depicted characteristics.

Question 4

Which one of the following is a characteristic of all insects?

Accepted Answer

They have six legs.. All insects, by definition, have six legs. Not all insects have tails or wings, and feathers are characteristic of birds, not insects.

Question 5

Study the picture below.
How many animal classification groups can you find in the above picture?

Accepted Answer

4. The image clearly depicts: 1. Mammals (giraffes, zebras), 2. Birds (flying birds, water birds like flamingos/storks), 3. Reptiles (turtles, alligator/crocodile), and 4. Amphibians (frog on lily pad). Fish are also present, which would make 5 groups. However, if 'fish' are not counted as 'above picture' or due to curriculum specific grouping, 4 is a possible interpretation (Mammals, Birds, Reptiles, Amphibians). Given the solution, 4 is the intended answer, likely excluding fish from the common classification for this context.

Question 6

The diagram below shows Animal K.
Which of the following statements below is not correct about the animal group that animal K belongs to?

Accepted Answer

All of them can live on land and in water.. Animal K is a fish. Fish belong to the animal group 'Fish'. Fish are aquatic animals and live exclusively in water; they cannot live on land. Options (1), (2), and (3) are generally true for fish.

Question 7

Alice wanted to conduct an experiment to find out which material allows most amount of light to pass through. She placed different material, one at a time, in front of the torchlight as shown below.
Which material is not correctly matched to its observation recorded in the table above?

Accepted Answer

Metal. The experiment tests light transmission. Metal is opaque and blocks light, so it should result in 'No light patch on the screen'. The table incorrectly states 'Bright light patch on the screen' for Metal. Glass is transparent (bright light), while rubber and ceramic are opaque (no light), which are correctly matched in the table.

Question 8

Study the flow chart below carefully.
Peri has a toy duck and she likes to play with it when she bathes. She likes to squeeze the floating duck to make a squeaking sound and throws it around.
Which of the following materials W, X, Y or Z is suitable to make the toy duck?

Accepted Answer

Y. A toy duck for bathing must be waterproof, strong (to be squeezed and thrown), and float. Following the flowchart:
- Z is not waterproof.
- X is waterproof but not strong.
- W is waterproof, strong, but sinks.
- Y is waterproof, strong, and does not sink (i.e., floats).
Therefore, Y is the most suitable material.

Question 9

Study the diagram of a car below.
Which of the materials below is not used to make parts of the car labelled above?

Accepted Answer

D: wood. A points to the car seat (fabric). B points to the car tire (rubber). C points to the car body (metal). D points to an interior panel or dashboard area. While wood can be used for decorative trim in some cars, it is generally not a primary material for the structural parts of a car body, tires, or seating labeled in this generic context. Wood is the material least commonly used for these labelled parts.

Question 10

Alan looked at the food in the glass jars.
Why was Alan able to see the amount of food left inside the jars?
The jars are ____.

Accepted Answer

transparent. To be able to see through an object to its contents, the material must be transparent. While glass jars are also rigid, strong, and waterproof, these properties do not explain visibility.

Question 11

Which of the following shows the correct stages of life cycle of a plant?

Accepted Answer

adult, seed, young. The typical life cycle of a plant begins with a seed, which germinates into a young plant (seedling) and eventually grows into an adult plant. 'Egg' and 'nymph' are terms associated with animal life cycles.

Question 12

Katie placed a seed in a container of soil as shown below. She watered the soil daily.
Which one of the following diagrams shows what Katie would observe after some time?

Accepted Answer

(Image of a seed with a shoot growing upwards, small leaves and roots growing downwards). After some time and daily watering, a germinating seed would have developed both a root system (growing downwards into the soil) and a shoot with leaves (growing upwards out of the soil). Option (4) depicts this stage of development.

Question 13

The diagram below shows the stages A, B, C and D of seed germination.
Light is needed at ____.

Accepted Answer

C and D only. Light is essential for photosynthesis, which is how a plant makes its own food using its leaves. Leaves appear in stages C and D. Stages A and B are early germination where the plant relies on stored food in the seed and primarily develops roots, not requiring light.

Question 14

Q, R and S are the stages in the life cycle of a mosquito.
Which of the following statements is correct?

Accepted Answer

Mosquito at stage Q is called a wriggler.. The life cycle of a mosquito is Eggs → Larva (Q) → Pupa (R) → Adult (S).
- (1) Larvae (Q) eat. (Incorrect)
- (2) Adult mosquitoes (S) lay eggs on water, not land. (Incorrect)
- (3) Mosquito larvae (Q) are commonly called 'wrigglers'. (Correct)
- (4) Pupae (R) do not eat. Larvae (Q) eat and moult. (Incorrect)

Question 15

The diagram below shows the life cycle of insects K and L.
Based on the information above only, which of the following statement(s) about the insect K and L is/are correct?
A The adult of L has six legs but the adult of K does not.
B The young of K resembles its adult but the young of L does not.
C The larva of K takes a longer time to become an adult than L.
D The egg of L takes a shorter time to become an adult than K.

Accepted Answer

C and D only. Both insects K and L undergo complete metamorphosis. All adult insects have six legs. In complete metamorphosis, the young (larvae) do not resemble adults.
- A: Incorrect. Both adult insects have six legs.
- B: Incorrect. In complete metamorphosis, young do not resemble adults.
- C: Correct. Larva K takes 21 days, Larva L takes 15 days. (21 > 15).
- D: Correct. Total time for K = 3+21+10 = 34 days. Total time for L = 5+15+5 = 25 days. (25 < 34).

Question 16

The diagram below shows the stages in the life cycle of a frog.
Which of the following correctly describes the organisms at stages S and T?

Accepted Answer

Stage S: has a tail; Stage T: has 4 legs. Stage S is a tadpole, and Stage T is an adult frog.
- (1) Tadpoles (S) have tails. Adult frogs (T) have four legs. (Correct)
- (2) Both tadpoles and adult frogs are able to swim. (Incorrect)
- (3) Tadpoles (S) breathe through gills. Adult frogs (T) breathe through lungs and skin. (Incorrect)
- (4) Tadpoles (S) live only in water. Adult frogs (T) live on land and in water. (Incorrect)

Question 17

The graph below shows the number of days in each stage of the life cycle of animal Y and animal Z.
At which stage would animal Y and animal Z be on the 20th day after the eggs hatched?

Accepted Answer

animal Y: Pupa; animal Z: Adult. From the graph:
- Animal Y: Larva stage lasts 12 days. Pupa stage lasts 8 days (from day 12 to day 20). So, on the 20th day, Animal Y is in the Pupa stage.
- Animal Z: Larva stage lasts 8 days. Pupa stage lasts 4 days (from day 8 to day 12). So, after day 12, Animal Z is in its Adult stage. On the 20th day, Animal Z is an Adult.

Question 18

Four students used the following methods to test if the metal Bar G shown below is a magnet.
Alice: Bring Bar G to one end of a magnet and if the magnet attracts it, then Bar G is a magnet.
Ben: Bring Bar G to one end of a magnet and if the magnet repels it, then Bar G is a magnet.
Clara: Suspend Bar G with a string and if it rests in the East-West direction, then Bar G is a magnet.
Diana: Suspend Bar G with a string and if it rests in the North-South direction, then Bar G is a magnet.
Which tests will help to identify if Bar G is a magnet?

Accepted Answer

Ben and Diana only. Repulsion is the definitive test for magnetism, as magnets repel only other magnets (like poles). Also, a freely suspended magnet aligns itself in a North-South direction.
- Alice's test (attraction) is not conclusive because a magnet can attract both other magnets and magnetic materials.
- Ben's test (repulsion) is conclusive.
- Clara's test (East-West alignment) is incorrect; magnets align North-South.
- Diana's test (North-South alignment) is conclusive.
Thus, Ben and Diana's tests are correct.

Question 19

Gina placed one pole of a magnet close to four different objects A, B, C and D. She observed what happened between each object and the magnet. She then recorded her observation by placing a tick (✔) in the appropriate boxes in the table below.
Which object A, B, C or D is a magnetic material but not a magnet?

Accepted Answer

A. A magnetic material (e.g., iron nail) is always attracted to a magnet but never repelled. A magnet will show both attraction (to an opposite pole) and repulsion (to a like pole).
- Object A: Only attracted. This indicates it is a magnetic material but not a magnet.
- Object B: Attracted and repelled. This means it is a magnet.
- Object C: Only repelled. This means it is a magnet.
- Object D: Neither attracted nor repelled. This means it is a non-magnetic material.
Therefore, Object A is a magnetic material but not a magnet.

Question 20

At first David placed a steel nail as shown in the diagram A below. David then moved the magnet from the other end of ruler towards the steel nail. The steel nail was attracted to the magnet as shown in the diagram B.
What is the distance moved by the steel nail?

Accepted Answer

5 cm. In Diagram A, the left end of the steel nail is at 0 cm. In Diagram B, the left end of the steel nail is at 5 cm. The distance moved by the steel nail is 5 cm - 0 cm = 5 cm.

Question 21

Christy conducted an experiment with some magnets to see how they attract to each other. Which of the following magnets arrangements is possible?

Accepted Answer

(Image of two magnets arranged S-N, touching). Magnets attract when opposite poles face each other (N-S or S-N). They repel when like poles face each other (N-N or S-S). For magnets to be touching and attracting, their poles must be opposite.
- (1) Shows S-N attraction, magnets touching. Possible.
- (2) Shows S-S repulsion, magnets touching. Impossible.
- (3) Shows N-N repulsion, magnets touching. Impossible.
- (4) Shows S-N attraction, magnets touching. Possible. 
Both (1) and (4) depict possible arrangements for attraction. Given one option must be chosen, (4) is selected as per standard answer keys, assuming it's the clearest representation or intended answer. In (4), the S pole of the top magnet faces the N pole of the bottom magnet, leading to attraction.

Question 22

Which of the following objects make use of magnets?
J Scrap iron crane
K Refrigerator door
L Door-stopper
M Aluminium spoon

Accepted Answer

J, K and L only. J (scrap iron crane) uses electromagnets to lift metal. K (refrigerator door) has magnetic seals. L (door-stopper) can use magnets to hold a door. M (aluminium spoon) is made of a non-magnetic material and does not use magnets.

Question 23

Mr Tan tried to open the door of a cage using an electromagnet as shown in the diagram below. When electricity was passed through the wire around Part A, Door B was attracted by Part A and swung opened. When the battery was removed, Door B closed.
Which of the following shows the correct materials used to make Part A and Door B?

Accepted Answer

Part A: Steel; Door B: Iron. Part A is the core of an electromagnet; it needs to be a magnetic material like steel or iron to become temporarily magnetized. Door B needs to be attracted by the electromagnet, so it must also be a magnetic material (iron, steel, nickel, or cobalt). Option (3) 'Part A: Steel; Door B: Iron' fits these requirements.

Question 24

Alice set up the following experiment to make an electromagnet using a battery and a wire coiled around the iron nail. She increased the number of coils around the iron nail and counted the number of steel clips that were attracted to it. Then, she recorded the results in the table below.
Which of the following table was Alice likely to get at the end of the experiment if she had successfully carried it out?

Accepted Answer

Number of coils: 10, 20, 30, 40; Number of steel clips attracted: 1, 3, 5, 8. The strength of an electromagnet is directly proportional to the number of coils of wire around its core. Therefore, as the number of coils increases (10, 20, 30, 40), the number of steel clips attracted should also increase. Option (2) shows an increasing trend (1, 3, 5, 8), which is consistent.

P3 Science SA2 2023 — Pei Hwa

Related papers