Question

Which one of the following is not a micronutrient?
(A) Boron
(B) Molybdenum
(C) Magnesium
(D) Zinc

Answer 1

Hint: Plants and animals need nutrients for proper functioning and regulation of their cells and other metabolic activities. The nutrients required are of varied quantities and proportions. Most of the nutrients are derived from food sources.

Complete answer:
Micronutrients are essential elements required to perform all the physiological functions of an individual to be healthy. As the name indicates, they are required in very small quantities. Humans need 100 milligram of micronutrients each day. Some of the types and functions of micronutrients are, as follows:
Fat-soluble vitamins: As the name indicates, these vitamins dissolve only in fats and not in water. So it is recommended to consume these along with food rich in fat. They are metabolised and stored in the liver to use later. Example: Vitamin A (proper vision), Vitamin K (blood clotting and bone development), Vitamin D (calcium absorption for bone growth and improves immunity), Vitamin E (protects cells from damage and improves immunity).
Water-soluble vitamins: They dissolve in water and are easily flushed out in urine. Hence, they cannot be stored, which makes it important for us to consume it every day through food. Example: Vitamin B (acts as coenzyme in important metabolic reactions), Vitamin C (synthesis of collagen and neurotransmitters).
Macro minerals: They are needed in more quantity than trace minerals to carry out important metabolic tasks. Example: Sodium, phosphorus, sulphur, potassium, chloride.
Trace minerals: These, also known as micronutrients, are required in lesser quantities than macro minerals. Example: Iron, manganese, copper, zinc, iodine, fluoride, selenium, boron etc.

Thus, (C) Magnesium is not a micronutrient.

Note:
Living organisms cannot produce the minerals in the micronutrients. They are obtained from the soil through plants. Calcium and iron are such minerals. Through the food chain, these minerals are utilised by different organisms. Adequate quantity of food has to be consumed to meet the daily nutrient requirement. Otherwise, it results in malnourishment.