C. Mammary gland. Hope this helps!
Answer: Amino acids share COMMON chemical groups but have UNIQUE side chains that allow for variation. The common groups are amino and CARBOXYL groups attached to an α carbon. Amino acids link together into a polypeptide via PEPTIDE bonds. Each polypeptide has a unique sequence. The repeating subunits interact with each other via hydrogen bonds to establish secondary structures. Interactions between the side chains determine the tertiary structure of the polypeptide. The combination allows for an almost infinite number of possible structures, each with a different function.
Explanation:
Pythons have jaws that are connected by flexible ligaments so they can stretch around large prey and then swallow it.
The surface area is used to get substances in or out through the cell's membrane.
Photosynthesis, respiration and combustion.
