A Protein is a complex molecule made up of amino acids which are responsible for specific and unique functions within the body.
Many people think that we simply need protein to build muscle, but in fact there are many different proteins that perform many different functions in the body.
Proteins
Globular proteins are soluble in water and tend to be involved in metabolic processes such as transportation and controlling biological processes.
Fibrous proteins are virtually insoluble in water. They tend to be involved in 'structure' and are usually involved in the creation of connective tissues, tendons and muscle fibres.