How Many Different Types of Amino Acids are Found in Proteins

Question

How many different types of amino acids are found in proteins?
A) 100
B) 200
C) 1,000
D) 20
E) 4

Accepted Answer

There are 20 different types of amino acids found in proteins. Each amino acid has a unique side chain, or "R group," that differentiates it from the others. The sequence and arrangement of these amino acids determine the structure and function of the protein.