Question

Mostly minerals are absorbed by a plant from the soil by a process which is

• A. Dependent on osmosis
  
• B. Dependent on water absorption
• C. Dependent on strength of solution
• D. None of the above.

Answer 1

Answer: (B), (C)

The correct options are
B Dependent on water absorption
C Dependent on strength of solution

In soil, the minerals can be present dissolved in soil solution or adsorbed on charged clay particles. Plants obtain minerals both from the soil solution (through absorption) as well as directly from clay particles (through ion exchange mechanisms). Mineral absorption can be active or passive. The passive mineral absorption can occur both in the direction as well as against a concentration gradient. Mass flow is one mechanism through which minerals are absorbed passively against their concentration gradient. In mass flow, mineral ions are swept into the root and passed into the plant parts along with the current of water, caused by transpiration pull. Mineral absorption depends on water absorption because the solvent of the soil solution is water. Mineral absorption can occur along with the water stream. Minerals can also be absorbed actively involving the expenditure of metabolic energy irrespective of the tonicity of the soil solution.

So, the correct answers are 'Dependent on water absorption and Dependent on strength of solution'.