Melanin, the pigment coloring skin, hair, and eyes, is primarily derived from Tyrosine. Tyrosinase converts Tyrosine to DOPA, which then transforms into melanin. This pathway protects skin cells from UV-induced DNA damage. Tryptophan and cholesterol are part of separate biochemical processes.
| List I (Enzyme) | List II (Function) |
|---|---|
| (A) Cytochrome oxidase | (I) Electron transport system |
| (B) Topoisomerases | (II) Change linking number |
| (C) Cohesins | (III) DNA Replication |
| (D) PCNA | (IV) Cell cycle |