Polypeptide chains undergo some modifications before they become fully functional. Some of these modifications include: proteolytic cleavage, lipidation and glycosylation. Proteolytic cleavage refers to the removal of some amino acids from a polypeptide chain by proteases in order for the protein to become active. An example of a substance that is modified through this process is insulin.
Answer:
carbon and three oxygen atoms
Answer is: each base can attch to only one other type of base
The skin plays a role in the production of vitamin D because when dehydrocholesterol reaches the skin by means of the blood and is exposed to ultraviolet light from the sun, it changes to vitamin D in an inactive form.
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