Question

A mushroom produces a funny looking blue pigment from the metabolic pathway shown below. OH Me Me OH OH OH OH HANE HAN HO HO HO OH O X1 HO OGDP X2 X3 HO HO Blue Cell OH HO OGDP EGT GDP HOOC You have two haploid mushrooms, both are white. You mate them. The diploid offspring are blue. The Punnett squares below show the genotype of the haploid parents and their progeny. Which image accounts for the experimental observations? ox, E (foto DIED AX AX2 А B с Band C O A only Bonly Conly

Answer 1

The correct option is B only.

For the production of blue pigment, the mushroom require all three enzymes. All three enzymes are present in B cross.

One parent contain gene for synthesis of X1 enzyme while the other parent contain genes for synthesis of X2 and X3 enzyme. So, the progeny contain enzymes for production of blue pigment.

In cross A, X2 and X3 enzyme producing gene is absent.

In cross C, X3 enzyme producing gene is absent.