Question

Root pressure is maximum when the

• A. rate of transpiration is high and the rate of absorption is very low
  
• B. rate of transpiration is very low and the rate of absorption is very high
  
• C. rate of absorption and transpiration is very high
  
• D. rate of absorption and transpiration is very low

Answer 1

The correct option is B

rate of transpiration is very low and the rate of absorption is very high

Root pressure is the transverse osmotic pressure within the cells of a root system that causes sap to rise through a plant stem to the leaves. Root pressure occurs in the xylem of some vascular plants when the soil moisture level is high either at night or when transpiration is low during the day.