Question

Mostly minerals are absorbed by the plant from the soil

• A. By a process dependent of water absorption.
• B. Only when soil solution is hypotonic to cell sap.
• C. Only when soil solution is hypertonic to cell sap.
• D. None of the above.

Answer 1

The correct option is A By a process dependent of water absorption.

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 direction as well as against 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 root and passed into the plant parts along the current of water, caused by transpiration pull.

Mineral absorption depends on water absorption because the solvent of soil solution is water. Mineral absorption can occur along with water stream. Minerals can also be absorbed actively involving expenditure of metabolic energy irrespective of the tonicity of soil solution.