Question

All elements that are present in a plant need not be essential to its survival. Comment.

Answer 1

Hint: Plants require minerals which are the inorganic elements chiefly obtained by them from the soil. These minerals are used for various absorption, distribution and metabolism processes and this is collectively called mineral nutrition in plants.

Complete answer: These minerals and elements are of paramount importance in the functioning and metabolism of plants. Some of these elements are the structural constituents of the plant body. The other functions are- influence the osmotic pressure of the cells, permeability of cytoplasmic membrane, provide toxic, catalytic or antagonistic effects.
The essential elements are divided into two categories:
Macronutrient or major elements- These must be present in the plant tissues in a concentration of more than 10 m mole per kg of dry matter. It includes carbon, hydrogen, oxygen, nitrogen, phosphorus, Sulphur, potassium, calcium and magnesium.
Micronutrients or trace elements- These are present in the plant tissues in a concentration less than 10 m mole per kg. It includes iron, manganese, copper, molybdenum, zinc, copper, zinc, boron, nickel and chlorine.
Besides these essential elements, plants also absorb certain elements that are not required for their survival like plants that grow near radioactive sites, accumulate radioactive metals in their parts. Some plants growing near mining sites, accumulate gold and selenium. These metals are not required by plants for their physiology and metabolism.
So, the correct answer is “Option A”.

Note: Nutrition can be described as the sum total of all the processes of uptake and utilization of raw materials by a living organism for its growth, development and maintenance. Plants require certain raw materials for this purpose that are called nutrients.