P5 Science CA2 2025 — Nan Hua

May put a stem with leaves into a beaker of red-coloured water. After one day, she cut the stem. The diagram below shows a cross section of the stem. Which one of the following correctly describes part X?

Which of the following statement is true?

The diagram below shows how digested food and gases are transported in the human body through systems Q and R. Gases X and Y are exchanged between systems Q and R. Which of the following best represents system Q, system R, gas X and gas Y?

A group of people was trapped in a lift. The graph below shows the changes in the amount of two different gases, G and H, in the lift. Which one of the following correctly identifies gas G and H?

The graph below shows the change in temperature of a block of melting ice over time. Based on the graph above, which of the following statement is correct?

(a) Name three parts found in the human respiratory system. [1] Kenneth wanted to find out how his average heart rate will change when he walks up the stairs. For the next three days, he walked up five floors of stairs at the same time each day. After each walk, he measured and recorded his heart rate. His resting heart rate is 80 beats per minute (bpm). The recorded data is as follows: Day 1 — 124 bpm, Day 2 — 126 bpm, Day 3 — 120 bpm. (b) Based on the results in the table, how did Kenneth's heart rate change when he walked up the stairs? Explain the change in his heart rate. [2]

The diagram below shows the movement of substances in the plant transport system. A and B represent different parts of a plant. The arrows show the direction of movement of water or food. (a) Identify the parts of the plant that A and B represent in the table below. [2] The diagram below shows a plant with an outer ring of the stem removed. Only the food-carrying tubes were removed. (b) Which part(s), X and/or Y, of the stem will likely become swollen after some time? Explain your answer. [2]

Sam set up a bottle garden as shown in the diagram. He poured in some water to ensure that the soil was moist so that his plants would have enough water before covering the bottle. Sam left the bottle garden under the sun for a few hours and noticed that there were some water droplets on the inner wall of the glass bottle. (a) Explain how the water droplets are formed. [2] (b) Sam's teacher told him that he should keep the bottle covered so that he does not need to water the garden for a long time. Explain why. [1]