Question

What is the difference between macro and micronutrients?

Answer 1

Hint: Plants need several nutrients and minerals in order to grow and perform metabolic activities. Plants absorb most of the minerals used by them from the soil with the help of roots. Based on the quantitative requirement of nutrients, they are divided into macro and micronutrients.

Complete answer:
The elements can be classified into two types which are required by plants. They are essential elements and non-essential elements. Keep in mind that there are three criteria That should be filled by an element in order to be called an essential element required by plants.
The element should be directly involved in the growth and metabolic activities of the plant and it should not be replaceable with any other element. The plant also must not be able to complete the life-cycle without this particular element. Only after fulfilling these criteria, an element is considered to be an essential element needed by plants.
-Elements that are needed by plants in large quantities are called macronutrients. They include carbon, hydrogen, nitrogen, phosphorus, oxygen, sulphur, potassium, magnesium, and calcium. Know that all the elements other than carbon, hydrogen, and oxygen are absorbed from the soil. Macronutrients are needed in large amounts, more than \[10mmoleK{g^{ - 1}}\]of dry matter. Nitrogen is needed by meristematic tissues and metabolically active cells in plants. It is present in proteins, vitamins, nucleic acids, etc. Phosphorus is present in cell membranes, nucleic acids, cell proteins etc. Potassium is needed for anion cation balance in-cells and also for protein synthesis. Calcium is needed for the formation of the mitotic spindle and cell wall synthesis.
-Nutrients that are needed by plants only in less amounts are called micronutrients. Examples of
micronutrients are iron, copper, manganese, molybdenum, zinc, boron, chlorine, and nickel. Micronutrients are needed in small amounts, less than \[10mmoleK{g^{ - 1}}\]of dry matter. Iron is present in proteins and also involved in electron transfer reactions. Manganese activates many enzymes for photosynthesis, respiration, and nitrogen metabolism. Copper is needed for the overall metabolism of plants. It is also involved in some redox reactions.

Note: There are groups of elements needed by plants other than essential elements and or called beneficial elements. They are mostly required by higher plants and include sodium, silicon, cobalt, and selenium.