Answer:
Amino acids
Step-by-step explanation:
Amino acids are protein monomers, in other words, an amino acid is the smallest unit that constitutes a protein.
Amino acids are present in various body functions, such as cell structure composition, tissue repair, nutrient transport, and immune functions.
In addition, amino acids can also be used as a source of energy for the body, such as carbohydrates and fats, but unlike them, amino acids have nitrogen (N) in their structure.