What are proteins formed from?

Proteins are formed from amino acids, which are organic compounds that serve as the building blocks of proteins. When proteins are synthesized in the body, amino acids are linked together in specific sequences to form polypeptide chains, which then fold into functional protein structures. There are 20 different amino acids that can be combined in various ways to produce a vast array of proteins, each with unique functions and characteristics.

Amino acids can be categorized into essential and non-essential amino acids. Essential amino acids must be obtained through diet since the body cannot synthesize them, while non-essential amino acids can be produced by the body. The specific sequence of amino acids in a protein determines its shape and function, making amino acids fundamental to the structure and activity of proteins.

The other options—fatty acids, vitamins, and carbohydrates—play different roles in the body and are not involved in the formation of proteins. Fatty acids are the building blocks of lipids, vitamins are organic compounds that are crucial for various biochemical functions, and carbohydrates serve mainly as energy sources and structural components. Thus, amino acids are the sole constituents from which proteins are formed, confirming that the correct answer is indeed C.