Proteins

PROTEINS.

Protein is one of the three main classes of food that provide energy to the body. The others are carbohydrates and fats. Proteins exist in every cell and are essential to plant and animal life. Plants build proteins from materials in the air and the soil. Human beings and animals obtain proteins from food. Foods high in protein include cheese, eggs, fish, and milk. All proteins contain carbon, hydrogen, nitrogen, and oxygen. Some proteins also contain iron, phosphorus, and suffur. Proteins are large complex molecules made up of smaller units called amino acids. Proteins make up a large part of each cell in the human body. Therefore, they are important in building, maintaining, and repairing tissues in the human body, especially bone cartilage and muscle. The body obtains most of its energy from carbohydrats and fats. However