Question

Most rapid water absorption is by which method?

• A. Passive absorption
• B. Salt absorption
• C. Active absorption
• D. Absorption by roots

Answer 1

The correct option is A Passive absorption

The absorption of water by the root cells of a plant occurs by two ways; (1) active absorption which involves, consumption of metabolic energy by the root cells for absorbing water and (2) passive absorption through the root cells which accounts for almost 98% of the total water absorbed by plants. Two factors are responsible for the rapid absorption of water via the passive method; (i) The cohesive and adhesive forces of water which create a continuous capillary stream in the xylem from the source (root) to the sink (leaves). (ii) The transpirational pull creates a diffusion pressure deficit (DPD) in the mesophyll cells of the leaf leading to tension in the leaves (sink). The tension is carried all the way to the xylem in the roots (source) forcing the root cells to absorb water rapidly. So, the correct option is A.