Principles of Inheritance and Variation Question 122
122. In Drosophila, the sex is determined by [2003]
(a) whether the egg is fertilized or develops parthenogenetically
(b) the ratio of number of X-chromosomes to the sets of autosomes
(c) $X$ and $Y$ chromosomes
(d) the ratio of pairs of X-chromosomes to the pairs of autosomes
Show Answer
Answer : b
Hints & Solution
(b) Calvin Bridges demonstrated that in Drosophila, the sex is determined by the ratio of the number of $X$ chromosomes to the sets of autosomes.