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.
Lastly, water also has a significance in the food chain. Producers which are mainly made up of water such as lettuce and leaves are relied on to provide water for consumers. Water has a huge biological importance for all living organisms as it is the building blocks to each individual organism. Without water, there may not even be the life forms we see on this earth today.