Transpiration — Paper 1 · IGCSE Biology (9-1) 0970

16 Petroleum jelly is waterproof and transparent. Covering the underside of the leaves of a plant with a thin layer of petroleum jelly will slow down the rate of water loss from the plant. Which statement explains this? A Plants absorb nutrients from the petroleum jelly. B Plants absorb water from the petroleum jelly. C Stomata are blocked by the petroleum jelly. D The petroleum jelly stops photosynthesis.

1 marks

Answer: C

This question in 0970/11 May/June 2018

35 A feature of some plants that live in dry places is that the leaves are reduced to spines. What is an advantage of the leaves being reduced to spines? A decrease in photosynthesis B decrease in transpiration C increase in photosynthesis D increase in transpiration

1 marks

Answer: B

This question in 0970/11 May/June 2018

16 The diagram shows two shoots at the start of an experiment on transpiration. shoot X shoot Y spring balance 30 g 30 g oil water What are the likely readings on the spring balances after three days? shoot X / g shoot Y / g A 25 25 B 25 30 C 30 25 D 30 30

1 marks

Answer: B

This question in 0970/12 Oct/Nov 2018

17 The table shows the rate of water flow through a tree over a 12 hour period. rate of flow time of day / cm per hour 17:00 100 19:00 120 11:00 140 13:00 250 15:00 300 17:00 260 19:00 180 What conclusion can be drawn from the table? A Between 7:00 and 17:00 hours the rate of flow continuously increases. B The greatest increase in rate of flow in a two-hour period is between 11:00 and 13:00 hours. C Water does not flow up through a tree at night. D Water flow is affected by humidity.

1 marks

Answer: B

This question in 0970/11 May/June 2019

15 The diagram shows an experiment to investigate transpiration. transparent plastic bag balance plant 1 plant 2 Plant 1 is not covered. Plant 2 and its pot are covered by a transparent plastic bag. The mass of each plant and its pot is measured. The masses are measured again after two hours. What is the result? A The mass of both plants decreases by the same percentage. B The mass of both plants stays the same. C The mass of plant 1 decreases more than the mass of plant 2. D The mass of plant 2 decreases more than the mass of plant 1.

1 marks

Answer: C

This question in 0970/12 Oct/Nov 2019

14 From which part of a leaf does most water evaporate during transpiration? A the cuticle B the guard cells C the spongy mesophyll cells D the xylem vessels

1 marks

Answer: C

This question in 0970/11 May/June 2020

14 From which part of a leaf does most water evaporate during transpiration? A the cuticle B the guard cells C the spongy mesophyll cells D the xylem vessels

1 marks

Answer: C

This question in 0970/12 May/June 2020

18 A plant shoot is placed in a solution of dye. The dye moves up the stem. Under which conditions will the dye move most slowly? temperature humidity A high high B high low C low high D low low

1 marks

Answer: C

This question in 0970/11 May/June 2021

18 Which graph shows the effect of increasing humidity on the rate of transpiration? A B rate of rate of transpiration transpiration humidity humidity C D rate of rate of transpiration transpiration humidity humidity

1 marks

Answer: C

This question in 0970/12 Oct/Nov 2021

18 The diagram shows a cross-section through a leaf. From which cell will most water evaporate during transpiration? A B C D

1 marks

Answer: D

This question in 0970/11 May/June 2022

13 In a leaf, water moves from the surface of a mesophyll cell and then out of the leaf into the atmosphere. What is the correct order of the processes involved? A active transport  osmosis B diffusion  evaporation C evaporation  diffusion D osmosis  active transport

1 marks

Answer: C

This question in 0970/12 May/June 2022

18 The apparatus shown can be used to investigate the effect of temperature and humidity on the rate of transpiration. plant pot polythene bag soil 500 g balance Which set of conditions would give the highest rate of transpiration and the greatest decrease in mass? temperature humidity A cool high B cool low C warm high D warm low

1 marks

Answer: D

This question in 0970/12 May/June 2022

18 Which process occurs during transpiration? A evaporation of water from the xylem B loss of water by osmosis from the guard cells C movement of water vapour through the spongy mesophyll by active transport D movement of water vapour through the stomata by diffusion

1 marks

Answer: D

This question in 0970/12 Oct/Nov 2022

17 Which pathway is taken by water through a plant? A root hair → root cortex → xylem → mesophyll → stomata B root hair → xylem → mesophyll → root cortex → stomata C stomata → root cortex → xylem → mesophyll → root hair D stomata → root hair → root cortex → xylem → mesophyll

1 marks

Answer: A

This question in 0970/12 May/June 2023

18 Which row shows the transpiration rate for the conditions described? atmospheric transpiration wind speed temperature rate A low low fast B high high slow C low high slow D low low slow

1 marks

Answer: D

This question in 0970/12 May/June 2023

16 From which part of a leaf does most water evaporate during transpiration? A the cuticle B the guard cells C the spongy mesophyll cells D the xylem vessels

1 marks

Answer: C

This question in 0970/12 Oct/Nov 2023

21 What is the pathway taken by water from the soil to the leaf? A root hair cells →root cortex →mesophyll →xylem B root hair cells →root cortex →xylem →mesophyll C root cortex→root hair cells →mesophyll →xylem D root cortex →root hair cells→xylem →mesophyll

1 marks

Answer: B

This question in 0970/11 May/June 2024

20 Which statement describes transpiration? A Water is pulled upwards by active transport. B Water is pulled up from the roots by phloem. C Water moves by osmosis inside the xylem vessels. D Water vapour diffuses out of the leaves.

1 marks

Answer: D

This question in 0970/12 May/June 2024

22 Some environmental factors are listed. 1 carbon dioxide concentration 2 temperature 3 oxygen concentration 4 wind speed Which factors directly affect the rate of transpiration? A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4

1 marks

Answer: D

This question in 0970/12 Oct/Nov 2024

16 The diagram shows the movement of water molecules from a plant leaf to its environment. Two processes have been numbered. 1 2 Which row identifies the numbered processes? process 1 process 2 A diffusion evaporation B evaporation diffusion C evaporation osmosis D osmosis evaporation

1 marks

Answer: B

This question in 0970/12 May/June 2025