Final answer:
Proteins contain a combination of 20 unique amino acids, which contribute to their diverse functions and structures. Some amino acids are essential and must be obtained from the diet, while others can be synthesized by the body. The unique combination and sequence of amino acids in each protein result in its specific shape and function.
Step-by-step explanation:
Proteins contain a combination of 20 unique amino acids. These amino acids are responsible for the diverse functions and structures of proteins. The amino acids are classified as essential or non-essential, depending on whether they need to be obtained from the diet or if they can be synthesized by the body.
For example, essential amino acids like leucine, tryptophan, and lysine cannot be synthesized by the body and must be obtained through food sources. On the other hand, non-essential amino acids like alanine, glutamine, and glycine can be produced by the body.
The different combinations and sequences of amino acids in proteins result in a wide variety of protein structures and functions. Each protein has its own characteristic amino acid composition that gives it a unique three-dimensional shape and specific biological activity.