Biology 5090 · O Level · Coordination and response in plants
Coordination and response in plants — practice question
Fig. 3.1 shows a young tomato plant growing beside a window. Cells from two different positions in the stem are also illustrated. The cells at X divide continuously. They then enlarge, and some develop into mature cells such as the one shown from position Y.
(a)[2]
The cells at positions X and Y differ in size and shape. State two other differences between these cells.
(b)[3]
Explain how the movement of water molecules contributes to this rise in cell size.
(c)[5]
The tomato plant is reacting to the light. Name this response and explain the roles of auxin and cell elongation.
(d)[2]
Tomato plant cells have a diploid chromosome number of $24$. State the number of chromosomes that a cell from position Y will contain and justify your answer.
Worked solution & mark scheme
This 12-mark question has a full step-by-step worked solution and mark scheme. One marking point: “cell at Y contains chloroplasts / cell at X lacks chloroplasts” …