Respuesta :
Answer: D.long chains of amino acids used for building, repair, and maintenance.
Explanation:
- Amino acids are organic compounds that consist of an amino group, a carboxyl group and a side chain in their basic structure.
- When the amino acids join together and form long chains, then they are responsible for the building of proteins. Thus, the proteins are made of one or more long chains of amino acids.
- Proteins perform many essential functions -
1. They perform the function of building various structural components such as hair, nails etc.
2. They perform the function of repair, for example, tissue damaged due to exercise.
3. They are also responsible for routine maintenance of cells and tissues.