Question

If a parent yeast is of mating type a, what will be the mating type of its bud?

(a) a

(b) alpha

(c) rho

(d) a-alpha

The question was posed to me in examination.

Origin of the question is Transcription in Eukaryotes : Gene Silencing at Telomere topic in chapter Gene Expression : Transcription Prokaryotes of Cytogenetics

Answer 1

Right answer is (b) alpha

Explanation: In yeast mating type alternates with every generation, so if a parent is ‘a’ then bud will be ‘alpha’ and vice versa. Yeast with a-alpha mating type is sterile while there is no rho mating type of yeast.