Question

Inorganic nutrients are present in the soil in the form of
(a) Molecules
(b) Atoms
(c) Electrically charged ions
(d)None of the above

Answer 1

Hint: Water and minerals ions are inorganic material present in the soil. The root hair absorbs the mineral by passive absorption to outer space like intercellular space and cell wall but for absorption into the inner space like cytoplasm and the vacuoles, it needs active transport which requires ions to create a concentration gradient.

Complete answer:
The electrically charged mineral ions help to maintain the concentration gradient and allow easy absorption through active transport. Inorganic substances, which form the majority of the soil solution, are commonly called minerals: those required by plants include nitrogen (N) and potassium (K) for structure and regulations. Plants are phototrophs, living in the inorganic environment taking carbon dioxide from the atmosphere and water and minerals from the soil. Their nutritional processes are traditionally grouped under two categories, organic and inorganic nutrition. The former involves the production of organic compounds by the incorporation of carbon, hydrogen, and oxygen through photosynthesis. The latter involves the acquisition of mineral elements from the soil.

Additional Information: -Chemical analysis of plant ash revealed that all about 90 odd elements form the constituent of plant material.
-A plant body may contain 50 of them. Some of them are essential for their growth and development.
-The others are called non-essential elements. Arnon and Stout have claimed 16 elements are essential for all higher plants.
So, the correct answer is 'Electrically charged ions'.

Note: - plants obtain essential elements from soil, water, and atmosphere. Of all essential elements, carbon, Hydrogen, and Oxygen are absorbed from soil solution and atmosphere.
-So, they are gradually non-mineral elements. Most of the others are released to the soil by weathering of rocks and are absorbed mainly as inorganic ions. So, they are called mineral elements.
-Nitrogen is available from both mineral and non-mineral sources.