Front

What are proteins?

Back

Large biomolecules or macromolecules consisting of one or more long chains of amino acid residues.

Front

What is a polypeptide?

Back

A linear chain of amino acid residues.

Front

What are peptides?

Back

Short polypeptides containing less than 20–30 residues.

Front

How are amino acids bonded together in proteins?

Back

By peptide bonds.

Front

What specifies the sequence of amino acid residues in a protein?

Back

The sequence of a gene, which is encoded in the genetic code.

Front

How many standard amino acids does the genetic code specify?

Back

20 standard amino acids.

Front

What are some functions of proteins?

Back

Enzymes that catalyze biochemical reactions, structural functions, cell signaling, immune responses, cell adhesion, and the cell cycle.

Front

What are amino acids composed of?

Back

Amine (-NH2), carboxyl (-COOH), and a side-chain (R group) specific to each amino acid.

Front

What is the N-terminus of a protein?

Back

The end with a free amino group.

Front

What is the C-terminus of a protein?

Back

The end with a free carboxyl group.