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 our lifeline that bathes us and feeds us. In ancient cultures water represented the very essence of life. The Romans were the first to pipe water into their growing cities, especially with their aqueducts.
Water Water is clearly the most important nutrient and the most abundant substance in the human body. Water comprises about three quarters of the human mass and is a major component in every cell. In addition water is important to human health for many reasons including but not limited to the following: â¢ Water is needed to separate (by a process called hydrolysis) a phosphate group from adenosine triphosphate (ATP) or guanosine triphosphate (GTP) to get energy as illustrated by the following equations.