Question

Root pressure is maximum when
(a) transpiration is high and absorption is very
low
(b) transpiration is very low and absorption is
very high
(c) absorption is very high and transpiration is
very high
(d) absorption is low and transpiration is also
very low

Answer 1

Answer:

c is the correct answer

Answer 2

Answer is option "b"

Explanation:

• When transpiration is low and soil is generally well watered, a positive root pressure develops. Under the influence of positive root, pressure water oozes out from ends of xylary elements in plants. The main reason for the development of positive root pressure is the active absorption of minerals and water by roots.
• Stephentiales (1727) coined the term root pressure. Root pressure is developed when rate of water absorption is more than the rate of transpiration.
• Hence, the right answer is option b "transpiration is very low and absorption is very high".