Chemically, protein is composed of amino acids, which are organic compounds made of carbon, hydrogen, nitrogen, oxygen or sulfur. Amino acids are the building blocks of proteins, and proteins are the building blocks of muscle mass, according to the National Institutes of Health (NIH).

DNA is made of chemical building blocks called nucleotides. To form a strand of DNA, nucleotides are linked into chains, with the phosphate and sugar groups alternating. The four types of nitrogen bases found in nucleotides are: adenine (A), thymine (T), guanine (G) and cytosine (C).

The basic building block of a protein is called an amino acid. There are 20 amino acids in the proteins you eat and in the proteins within your body, and they link together to form large protein molecules. The variety of ways they mix and match allows for the great diversity of proteins in nature.

Proteins. Like the carbohydrates, proteins are composed of smaller units. The monomers that make up proteins are called amino acids.

Amino acids are the monomers that make up proteins. Each amino acid has the same fundamental structure, which consists of a central carbon atom bonded to an amino group (–NH2), a carboxyl group (–COOH), and a hydrogen atom.

There are four main types of monomer, including sugars, amino acids, fatty acids, and nucleotides.

Biomacromolecules are large biological polymers, such as nucleic acids, proteins, and carbohydrates, that are made up of monomers linked together. For example, proteins are composed of monomers called amino acids.

Protein synthesis is the process in which cells make proteins. It occurs in two stages: transcription and translation. Transcription is the transfer of genetic instructions in DNA to mRNA in the nucleus. It includes three steps: initiation, elongation, and termination.

Because there are only 20 different amino acids but 64 possible codons, most amino acids are indicated by more than one codon. (Note, however, that each codon represents only one amino acid or stop codon.)