1. Where does water evaporate from in the leaf? [1 mark]

2. What is the effect of high humidity on the rate of transpiration? [1 mark]

3. What causes water to move up the xylem vessels? [1 mark]

4. Which surface of a leaf typically has more stomata? [1 mark]

5. What happens to stomata in the dark? [1 mark]

6. Explain the mechanism of water movement through the leaf from the xylem to the atmosphere. [4 marks]

7. Explain why wilting occurs in plants when water loss exceeds water uptake. [3 marks]

8. Explain how wind speed affects the rate of transpiration. [3 marks]

9. Describe and explain the effect of increasing temperature on the rate of transpiration. [4 marks]

10. Explain why transpiration is important for plants, other than cooling. [3 marks]

11. Describe how to use a potometer to measure the rate of transpiration. [4 marks]

12. Why is it important to cut the shoot underwater when setting up a potometer? [2 marks]

13. A student investigates the effect of light intensity on transpiration rate using a potometer. State the independent variable, dependent variable, and two control variables. [4 marks]

14. A potometer experiment produced the following results: Time (min): 0, 5, 10, 15, 20 Distance (mm): 0, 12, 24, 36, 48 Calculate the rate of water uptake in mm/min and describe the pattern shown by the results. [3 marks]

15. A student wants to investigate the effect of wind on transpiration. Suggest how they could create different wind speeds using a potometer setup. [2 marks]