Question

The gene "C" which controls the expression of coat colour in rabbits codes for the enzyme X which acts on the substrate Y to synthesize the product Z.

X, Y and Z stand for:

• A. X - Tyrosine, Y - Melanin, Z - Eumelanin
• B. X - Tryosinase, Y - Tyrosine, Z - Melanin
• C. X - Melanase, Y - Melanin, Z - Eumelanin
• D. X - Tyrosine, Y - Tyrosinase, Z - Melanin

Answer 1

The correct option is B X - Tryosinase, Y - Tyrosine, Z - Melanin

The gene "C" which controls the coat colour in rabbits, encodes an enzyme called tyrosinase, which is the first enzyme in a metabolic pathway that leads to the synthesis of melanin from the substrate, the amino acid tyrosine.

This pathway results in the formation of two forms of melanin. Eumelanin, a black pigment, is made first, and then phaeomelanin, an orange/yellow pigment, is made from eumelanin.