Are proteins capable of being functional, such as hormones or enzymes?

Proteins are indeed capable of being functional, and they serve many vital roles in biological systems. They can act as enzymes, which are catalysts that speed up chemical reactions in the body, and they can also function as hormones, which are signaling molecules that regulate various physiological processes. The structure of proteins, determined by their amino acid sequences, allows them to fold into specific shapes that are necessary for their function. For example, the specific arrangement of amino acids in an enzyme's active site is crucial for its ability to bind to substrates and catalyze reactions. Likewise, hormones often have specific binding sites that interact with target cells to elicit a biological response.

This highlights the versatility of proteins, as they are not limited to just structural roles but can also be critical in catalytic and regulatory functions within both plants and animals.