Proteins are important for the growth and repair of the cells of our body. Without proteins, humans are susceptible to deadly diseases. Red meat, beans, soy products, poultry and dairy products are rich sources it.
Imagine proteins to be a long chain of beads. These beads are nothing but what are called amino acids. The amino acids join in different ways to form different proteins. They are therefore complex, organic compounds composed of many amino acids linked together through bonds. Amino acids are thus the building blocks of it.. These have an influence on the function of organs, glands, tendons and arteries. These acids are organic in nature. They consist of several structural units. The structures are grouped as primary, secondary, tertiary and quaternary based how the amino acids are linked.
When food containing proteins is eaten, the digestive system breaks them down into small units of amino acids. The amino acids are used again to make proteins. This complex biological process is called protein biosynthesis. All organisms need some of it, whether they are used in muscles or as simple structures as in the cell membrane. Though there are about 50 kinds of amino acids, scientists have discovered that there are about 20 amino acids that are used to make protens in the body.
Amino acids are either synthesized by the body itself or must be supplied in the diet. Out of the 20 amino acids, 9 are defined as essential amino acids which have to be supplied in the diet. The remaining 11 can be produced by the body itself. Numerous combinations of these 20 amino acids make different kinds of proteins. Protens are available in most of the cells including the skin, hair, muscles, tendons, ligaments. They provide structure to the body of multi-celled organism. They also help catalyze, regulate and protect the body metabolism in the form of enzymes, antibodies etc.
Proteins are classified as simple, conjugated and derived proteins. On hydrolysis, simple proteins like albumins, globulins etc yield only amino acids. Hemoglobin, glycoprotein etc are conjugated proteins that are simple proteins combined with non-protein substance in the body. Peptides are derived proteins that are derived from simple or compound proteins by physical or chemical means.