Protein One of the three main classes of food. Proteins are large, complex molecules made of amino acids, which are called the building blocks of the cells. The cells need proteins to grow and to mend themselves. Protein is found in many foods such as meat, fish, poultry, and eggs. The sequence of the amino acids, and thus the function of the protein, is determined by the sequence of the base pairs in the gene that encodes it.
Proteins are essential to the structure, function, and regulation of the body.
Examples are hormones, enzymes, and antibodies. The protein molecule assembled under the direction of a gene. Proteinuria Too much protein in the urine. This may be a sign of kidney damage. The normal, pre-cancerous equivalent of the oncogene.