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Protein is an essential nutrient whose name comes from the Greek word protos, which means “first.” To visualize a molecule of protein, think of a very long chain. The links in the chain are amino acids, commonly known as building blocks of protein. In addition to carbon, hydrogen, and oxygen atoms, amino acids contain a nitrogen group. The amino group is essential for synthesizing specialized proteins in your body.
The human body is full of proteins. There are proteins in the outer and inner membranes of every living cell.
Your hair, your nails, and the outer layers of your skin are made of protein Keratin, Keratin is a hard protein, a protein resistant to digestive enzymes. So if you bite them you can’t digest them.
Muscle tissues contain myosin, actin, myoglobin, and a number of other proteins.
Bone has lots of protein. The outer part of bone is hardened with minerals such as calcium, but the basic, rubbery inner structure is protein, and there is also protein in bone marrow.
Red blood cells contain hemoglobin, a substance that carries oxygen through the body; globin is a protein.
Your body uses protein to build new cells, maintain tissues, and synthesize new proteins. About half the dietary protein you consume each day goes to make enzymes. The specialized worker proteins that do certain jobs like digesting foods and assembling or dividing molecules to make new cells and chemical substances. To do these functions, enzymes often need specific vitamins and minerals.
Your ability to see, think, hear, move- or to just about anything that is part of living a healthy life- requires your nerve cells to send messages back and forth to each other or to other cells like muscle cells. Sending these messages chemicals called neurotransmitters are needed, and making them requires proteins.
They are a big part of every new cell and every new individual, because DNA and RNA contain proteins.
The cells in your digestive tract can only absorb single amino acids or very small chains of two or three amino acids called peptides. So proteins from food broken are broken into their component amino acids by digestive enzymes- which are specialized proteins. The other enzymes in your body synthesize new proteins by reassembling amino acids into specific compounds that your body need to function. This process is called protein synthesis.
Amino acids hook up with fats to form lipoproteins, the molecules that ferry cholesterol around and out the body. Or the amino acids may join up with carbohydrates to form glycoproteins found in the mucus of the digestive tract.
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