CIE iGCSE Co-Ordinated Science B8.3 Transpiration Exam Style Questions Paper 1
Question
In which conditions will the rate of transpiration be greatest?
A 10 C and high humidity
B 10 C and low humidity
C 30 C and high humidity
D 30 C and low humidity
▶️Answer/Explanation
Ans :C
Question
Which changes increase the rate of transpiration?
1 increasing temperature
2 increasing humidity
3 decreasing temperature
4 decreasing humidity
A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4
▶️Answer/Explanation
Ans :A
Question
Where does evaporation of water occur during transpiration?
A from the air spaces through the stomata
B from the phloem
C from the surfaces of mesophyll cells
D from the xylem
▶️Answer/Explanation
Ans :C
Question
The diagram shows a shoot at the start of an experiment investigating transpiration. The mass of the shoot, measuring cylinder, water and oil is measured.
The apparatus is left for three days and then the mass recorded for a second time.
Under which conditions would there be the most loss of mass from the apparatus?
▶️Answer/Explanation
Ans : B
Question
The rates of water uptake and loss are measured in four leaves. The results are shown in the table.
Which leaf is least likely to wilt?
▶️Answer/Explanation
Ans: D
Question
Which conditions cause the highest rate of transpiration in a plant?
▶️Answer/Explanation
Ans: A
Question
In which weather conditions is the rate of transpiration fastest?
A. cold and dry
B. cold and wet
C. warm and dry
D. warm and wet
▶️Answer/Explanation
Answer: C
Explanation: Transpiration is the process by which water is lost from plants through evaporation. It is fastest in warm and dry conditions because higher temperatures increase the rate of evaporation, and dry air increases the water potential gradient between the leaf and the atmosphere, driving more water loss.
Question
Under which conditions will transpiration from a plant be fastest?
| temperature | humidity | |
|---|---|---|
| A | high | high |
| B | high | low |
| C | low | high |
| D | low | low |
▶️Answer/Explanation
Answer: B. high, low
Explanation: Transpiration is the process of water movement through a plant and its evaporation from aerial parts, such as leaves. High temperature increases the rate of evaporation, and low humidity means the air can hold more water vapor, both of which increase the rate of transpiration.
Question
What pathway is taken by water molecules as they move through a plant?
A. mesophyll cells → xylem vessels → root cortex cells
B. root cortex cells → mesophyll cells → xylem vessels
C. root cortex cells → xylem vessels → mesophyll cells
D. xylem vessels → root cortex cells → mesophyll cells
▶️Answer/Explanation
Answer: C. root cortex cells → xylem vessels → mesophyll cells
Explanation: Water is absorbed by the root cortex cells, then transported through the xylem vessels to the mesophyll cells in the leaves, where it is used in photosynthesis.
Question
Transpiration is the process by which water moves through a plant. From which cells in the leaf does most of the water evaporate and through which structure is it lost as water vapour to the atmosphere?
▶️Answer/Explanation
Answer: D
Explanation: Most of the water evaporates from the mesophyll cells in the leaf and is lost as water vapour through the stomata, which are small openings on the underside of the leaf.