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 Important for Life. Some of the Earthâs water supply is temporarily locked up within the many lifeforms found across the Earthâs biosphere. This water makes up a majority of most organisms, and is a critical component, making the processes of life possible.