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.
Why is water so important to life? It all has to do with the unique properties that water exhibits. Firstly, it is the only substance on Earth that is in liquid form at the temperatures commonly found on the Surface of our planet. Secondly, it is a superb solvent, meaning that other substances regularly and easily dissolve into it. This allows water to carry nutrients to cells, and carry waste away from them.