In general, foods are made up of carbohydrates, proteins, and fats, each of which provide a different number of calories: 1  Carbohydrates provide 4 calories per gram. 2  Proteins provide 4 calories per gram. 3  Fats provide 9 calories per gram.
Importance of Water. Water is used for various important purposes: Water in Agriculture. Water plays the most important role in agriculture. Agriculture is impossible without irrigation throughout the crop season. Irrigation ensures proper plant growth.
Water is essential for life, health and human dignity. In extreme. emergency situations, there may not be sufficient water. available to meet basic needs and in these cases, supplying. a minimum level of safe drinking-water for survival is of. critical importance.