The tapetal layer is of great physiological significance as all the food material entering into the sporogenous tissue diffuses through this layer. Ultimately the cells of tapetal layer disorganise. Thus, tapetum makes a nutritive layer for the developing microspores or pollen grains.

An essential nutrient is a nutrient that the body cannot synthesize on its own  or not to an adequate amount and must be provided by the diet. These nutrients are necessary for the body to function properly. The six essential nutrients include carbohydrates, protein, fat, vitamins, minerals and water. Carbohydrates are the main energy source for the brain. Protein is the major structural component of cells and is responsible for the building and repair of body tissues. Fat is an energy source that when consumed, increases the absorption of fat-soluble vitamins including vitamins A, D, E and K. 

Nutrients give energy and keep your body running. Nutrients help build and strengthen bones, muscles, and tendons and also regulate body processes. Therefore, (d) is the correct answer.

For various interconnected activities taking place in the body, the energy and raw material is provided in the form of food. Therefore, (a) is the correct answer.

The meal that includes all the nutrients namely, carbohydrates, proteins, fats, vitamins and minerals in a required balanced proportion is known as a balanced diet.

Nutrients are substance present in food and essential to life and health. They provide energy, building blocks for repair and growth and are necessary to carry out a chemical process.

Nutrients are substance present in food essential to survive, growth and health. They include macronutrients i.e, consumed in large amounts like carbohydrates, proteins and fats. And micronutrients i.e consumed small amounts like vitamins and minerals.

Nutrients are compounds in food, essential to life and health, providing us with energy, a building block for repair and growth and substance necessary to regulate the chemical process.

Nutrients are essential to survive and grow for an organism. A balanced diet provides the body nutrients it needs to function properly. Hence, a balanced diet is a good source of nutrients.

The process of nourishing or being nourished, especially the process by which a living organism assimilates food and uses it for growth and for replacement of tissues

•  The four major structural elements in the human body by weight  (oxygen, hydrogen, carbon, and nitrogen), are usually not included in lists of major nutrient minerals.
• As a group, minerals are one of the four groups of essential nutrients, the others of which are vitamins, essential fatty acids, and essential amino acids
• The five major minerals in the human body are calcium, phosphorus, potassium, sodium, and magnesium All of the remaining elements in a human body are called "trace elements". The trace elements are sulfur, iron, chlorine, cobalt, copper, zinc, manganese, molybdenum, iodine and selenium. Hence, silicon is not a major nutrient for the body.
  

• Physiological calories obtained from different food substances are - Carbohydrates give 4.0Kcal/g, Proteins give 4.0Kcal/g while fats give 9.0Kcal/g.
• So, energy from 5g sugar = 5 x 4Kcal = 20Kcal
• Energy from 4g albumin = 4 x 4Kcal = 16Kcal
• energy from 10g+2g fat = 12 x 9Kcal = 108Kcal
• lignin cannot be digested by humans because of the absence of digestive enzyme for lignin so no calories will be obtained from them. Ruminants are capable of digesting lignin.
• Adding all the above-obtained values we get 144Kcal.

So, the correct answer is '144'.