P6 Science SA2 2025 — Rosyth

Ali made the following observations about animal K. • lives on land • gives birth to young alive • has hair as outer covering • feeds on the mother's milk when young Based on his observations, which animal group does K belong to?

Organism Z is found at the surface of water on a sunny day. The picture below shows how it looks like under the microscope. Devi concluded that it is a plant cell. Which parts of the organism led her to that conclusion?

A plant is shown in the diagram below. X, Y and Z represent different parts of the plant. Which of the following is correct? [Table options pair each part with a function]

The diagram below shows the human digestive system. Identify the function of part Y of the human digestive system.

Mr Foo wanted to grow a new plant by using different parts from plants A and B. He cut out the upper part of A and the lower part of B. Then, he put the two parts together and bound them with cloth as shown in the diagram below. Mr Foo watered the soil every day. After two weeks, he observed: • new plant was growing upright • new leaves growing on the upper part of A • longer roots growing on the lower part of B Based on Mr Foo's observations, which of the following statements is true?

The diagram below shows the flow of blood in humans and fish. Which blood vessels, A, B, C, D, E, F and G, carry blood rich in oxygen and blood rich in carbon dioxide?

The diagram below shows the life cycles of two organisms, P and Q. Based on the information provided, which of the following statements below is true about the two organisms above? A Both have a three-stage life cycle. B Both of their young look like their adults. C Organism P develops into an adult faster than organism Q.

The diagram below shows the different stages of germination in a seed. Which of the following stage(s), A, B, C, D, would the plant be able to make its own food?

The chart below shows the process of fertilisation when cell A from the ovary fuses with cell B from the testis in the human reproductive system. Which one of the following correctly identifies cells A and B?

Under different conditions, plant R opens and closes its leaves as shown in the pictures below. Fandi recorded his observations of how the leaves responded to different environmental conditions as shown in the table below. [Table: Temp high+Light high → open ; Temp high+Light low → close ; Temp low+Light high → open ; Temp low+Light low → close] Based on the information above, which of the following most likely explains why the leaves responded to the different environmental conditions?

Trees A and B are of the same type. The flowers behave differently throughout the day as shown in the pictures below. The flowers are visited by pollinators throughout the day. A farmer grew trees A and/or B on three similar plots of land, L, M and N as shown below. [Table: Plot L — tree A × 20 ; Plot M — tree B × 20 ; Plot N — tree A × 10 and tree B × 10] Based on the information above, which option shows the correct order of plots, starting with the one having the most number of flowers pollinated between 7 am and 7 pm?

The picture below shows Bird W. Bird W has the following adaptations: • rides air currents to conserve energy while flying over the sea • has special glands at eyes to remove salt • has sharp and hooked beak to catch prey • follows boats to get food Which of the following identifies the structural and behavioural adaptations correctly?

Habitat Z only had organisms, P, Q and S, at first. Organism R was introduced later. The food web below shows the relationship among organisms P, Q, R and S. The graph below shows the number of organism S over a period of time. [Figure: line graph of number of organism S vs time — flat at A, drops sharply to a low B, rises sharply to a high C, then settles slightly lower at D] At which point, A, B, C or D, was organism R likely to be first introduced?

Organism Q lives at the gills of the fish and can only be seen under a microscope. Organism Q causes the fish to develop larger gills. Such fish are often found near the surface of the water. Based on the information above, which of the following best explains why organism Q caused the fish to develop larger gills?

The diagram below shows a circuit containing three rods, X, Y or Z. There are two metal rods and a plastic rod. Which of the following identifies the material of the rods correctly to light up the bulb in the circuit?

Jason placed a glass of tap water on a hot plate and measured its temperature for 10 minutes. The graph below shows his results. Which of the following is true about the water at PQ?

The diagram shows the water cycle. Which of the following statements is correct?

James filled a measuring cylinder with 30 cm³ of plasticine. Next, he added water until it reached the 300 cm³ mark. He left the set-up in the classroom. After a few days, the water level decreased to the 290 cm³ mark. Which of the following is most likely the final volume of the plasticine and water?

Susan lowered an inverted glass over a small floating object in a basin of water until the glass touched the bottom of the basin as shown below. Which of the following explains why the water level inside the glass was lower from the water level in the basin?

Ryan has a can containing 150 ml of juice. He crushed the can without spilling any juice as shown below. Which of the following about the can of juice is correct?

Jerry has two soup containers, L and M, made of different materials. He poured an equal volume of hot soup into each container. Container L felt hot to his touch but not container M. In which container should he put hot food to keep it warm and cold drinks to keep them cool?

Which of the following diagrams correctly shows the direction in which light travels for the doctor to see Mei's face?

A boy stood in front of the mirror. He could not see the soccer ball behind him. Which one of the following was the reason why he could not see the ball?

Miss Lim had four bar magnets, P, Q, R and S. She wanted to compare the strengths of the bar magnet by putting each of them above a tray of pins as shown in the diagram below. The table below shows the number of pins attracted by each magnet from different distances away from the pins. [Table: P — 7 cm away → 9 pins; Q — 3 cm away → 9 pins; R — 9 cm away → 13 pins; S — 3 cm away → 13 pins] Which of the following statements is correct?

Anjay made a game as shown below. The rod with bars A and B were used to pick up objects, T, U and V. Anjay made the following observations: • bar A could pick up objects T and V only • bar B could pick up objects T and U only Which of the following correctly shows what bars A and B? [Figure: option diagrams of A and B as either magnets with N/S labels or iron bars]

An experiment was conducted using springs A and B. Different loads were hung on each spring one at a time. The lengths of the springs were recorded in the graph below. Which of the following are correct conclusions that could be drawn from the experiment?

At her graduation ceremony, Aisha threw her hat into the air. Which of the following statements is true when the hat is being thrown into the air, from height X to Y?

When the circuit is closed, the bar magnet moved from position A to B as shown in the diagram below. Which of the following shows the conversion of energy that explains the movement of the bar magnet from position A to B when the circuit is closed?

The following shows the information of a food chain in a forest. • Y is a prey of Z. • Y is a plant-eater. • W is the producer. • X is a predator of Z. (a) Construct a food chain using the above information. [1] (b) Explain the change in the population of organism Y if a disease wipes out the population of organism X. [1]

Plant M is found growing high on the branches of trees. The image below shows the enlarged image of plant M with its roots growing into a tree branch. (a) How does plant M get water to survive? [1] Birds eat the fruits of plant M. The seeds that pass through their digestive system are sticky. (b) Explain how the sticky outer covering of the seeds helps plant M to grow on the high branches of trees. [1] (c) How does growing on the high branches of trees help plant M to survive better? [1]

Birds A and B often live in groups. They use sounds to communicate and attract their mates. The table below shows the volume of sounds made by birds A and B. For the birds to hear one another, the average volume of the noise in the habitat must be lower than the volume of the sound made by the birds. The table below shows the average volume of noise measured in a habitat where both birds are found. [Table: 6 am–7.59 am — 42; 8 am–9.59 am — 65; 10 am–11.59 am — 70; 12 pm–1.59 pm — 75] (a) Using the above information, tick (✓) the time range that is most suitable for bird A to communicate with one another. [1] The graph below shows the number of nests built by birds A and B in habitats with different volumes of noise. [Figure: line graph — bird A line slopes down from 15 nests at 45 units to about 6 nests at 70 units; bird B line stays roughly flat at about 10–11 nests across all noise volumes] (b) Based on the graph, how did the population of A change as the average volume of noise in its habitat increased? Explain your answer. [1] The number of nests built by bird B is not affected by the volume of noise in its habitat as it has other adaptations to attract its mates. (c) Apart from mating calls, suggest another possible adaptation that allowed bird B to attract its mates. [1]

The diagram below shows the air sacs of the lungs of a non-smoker and a smoker. Substance T sticks to the surface of the lungs of a smoker. A study was done with two men, A and B, to measure the amount of oxygen absorbed into their blood. The results are shown in the bar graph below. [Figure: bar graph — man A: tall bar (more oxygen absorbed); man B: shorter bar (less oxygen absorbed)] (a) Based on the above information, explain why man B is more likely to be a smoker. [2] The bar graph below shows the heart rates of man A and man B when they do different activities. [Figure: bar graph showing heart rates (beats per min) — walking: small bar for A, slightly larger bar for B; running: very tall bar for B (A's running bar not shown)] (b) Draw a bar to show the heart rate for man A when he runs at the same speed as man B. [1] (c) Explain why the heart rate increases for man B when he runs. [1]

Plant P is found in a rainforest. The fruit of plant P is shown in the picture below. During the dry season, the seeds of parent plant P are dispersed in the following pattern. [Figure: map view — forest with parent plant P in centre; seeds scattered in a small circle close to P; a river flows along the top edge but seeds are not in the river] (a) State the seed dispersal method for plant P during the dry season. [1] The seeds of plant P have a fleshy outer covering. [Figure: enlarged seed showing fleshy outer covering] During the rainy season, the river overflows and floods the forest. After the river returns to its normal level, a different dispersal pattern is observed for the seeds of plant P as shown below. [Figure: during the rainy season — parent plant P stands in flooded forest. After the rainy season — seeds are spread widely across the forest, far from parent plant P] (b) Using the above information, state the method of dispersal for the seeds of plant P during the rainy season. Explain your answer. [2] (c) Explain why it is more advantageous for plant P to disperse its seeds during the rainy season. [1]

The diagram below shows set-up P which was placed near the window from 6 am to midnight. (a) The graph below shows the change in the amount of gases in set-up P throughout the experiment. Label the gases in the boxes provided. [2] [Figure: graph of gas amount in set-up P vs time from 6 am to midnight. One line (solid) starts high, dips around noon, then rises and stays high after 6 pm — labelled (i). Another line (dashed) starts low, rises to peak around noon, then falls and stays low — labelled (ii).] (b) Identify the changed variable in the experiment. [1] He prepared another similar set-up Q and left it under the sun for the same amount of time as set-up P. [Figure: similar set-up but the glass jar is painted black, placed under the sun] (c) How would the amount of carbon dioxide in set-up Q change at the end of the experiment? Explain your answer. [2]

Kim conducted an experiment to compare four materials, A, B, C and D. The number of 1-kg weights needed to break each material was counted. (a) Which property of the material is being tested? [1] (b) Based on Kim's results, which material, A, B, C or D, is most suitable to make the shelves for keeping the books in the library? Explain your answer. [2]

Benny turned on the hot water shower as shown in the picture below. After a while, he noticed substance A forming near the shower head. (a) What state of matter is substance A in? [1] (b) Explain how substance A was formed. [2]

Sally conducted an experiment using the set-up as shown below. (a) Explain why the reading on the spring balance increased when the switch was closed. [2] Sally changed the number of batteries in the above set-up and recorded the readings on the spring balance in the table below. [Table: 2 batteries — 1.0, 1.1, 1.2 ; 3 batteries — 1.5, 1.6, 1.4 ; 4 batteries — 2.4, 2.6, 2.2] (b) Why did Sally repeat her experiment? [1]

Shahim made a lantern with three light bulbs. The bulbs are controlled with a switch. (a) After one bulb fused, the other two bulbs did not light up when the switch was closed. Explain why. [1] Shahim constructed a new circuit in the lantern using three new bulbs, X, Y and Z, and a switch. The bulbs work as described below: • If any one bulb fuses, the other two will still light up. • Three bulbs will light up only when the switch is closed. (b) The diagram below shows part of the new circuit. Complete the circuit so that it will work as described above. [2] (c) Based on the circuit arrangement in (b), what would happen to the brightness of bulbs X and Y if bulb Z fuses? [1]

Balls, X, Y and Z, are of the same size but have different masses. Kitson lifted them one at a time onto a table of 1 m high from the ground. The amount of energy he needed to lift each ball is recorded in the table below. [Table: Ball X — 4 kg — 70 units; Ball Y — 8 kg — 140 units; Ball Z — 12 kg — 210 units] (a) What is the relationship between the mass of the ball and the amount of energy needed to lift the ball up to the table? [1] Next, Kitson pushed ball Y off the table. [Figure: ball at position A on the table edge, position B in mid-air falling, position C on the floor] (b) Fill in the boxes to show the energy conversion when ball Y dropped from position A to C. [1] (c) Which ball, X, Y or Z, when dropped from the table, will produce the softest noise when it lands on the floor? Explain in terms of energy conversion. [2] In another experiment, Kitson pushed a few glass bottles of different masses off the same table and counted the number of pieces each glass bottle broke into. (d) State a possible hypothesis for his experiment. [1]

The diagram shows a wooden pathway in a park. Wire mesh is fitted on the wooden pathway to prevent people from slipping when they walk on it. (a) State the two forces acting on the people as they walked on the pathway. [1] During rainy season, rainwater is trapped by the wires as shown below. [Figure: close-up of wire mesh with rainwater puddled between the wires] (b) Explain why during rainy season, the wire mesh becomes slippery for people to walk on. [1] A visitor observed that dead leaves are often found near the plants growing along the pathway. After some time, dark patches were observed growing on the dead leaves. (c) Which group of living things do the dark patches belong to? [1] (d) How does the group of living things identified in (c) benefit the plants growing along the pathway? [2]