Question

Determine the sex (A, B, C, D) of Drosophila according to the chromosomal constituent give below:

	Chromosome constitution	Sex-Index
A.	AA + XO	A
B.	AA + XXX	B
C.	AAA + XXY	C
D.	AA + XY	D

	A	B	C	D
	Sterile male	Super female	Inter sex	Normal male
	Normal male	Super female	Inter sex	Normal male
	Sterile male	Super male	Inter sex	Inter sex
	Inter sex	Super female	Super male	Normal male

Answer 1

Hint:-The famous fruit fly is also known as Drosophila or vinegar fly. Drosophila has X, Y and autosomes chromosomes. The Y chromosome, unlike humans, does not impart maleness on them but rather encodes genes required for sperm development. Their sex is determined by the ratio of X chromosomes and autosomes.

Complete Answer:-The 'Super female' would be a Drosophila with XXXYY sex chromosome. Sex is mainly calculated in Drosophila by the X: A ratio, or the ratio of the number of X chromosomes to the number of autosome sets. On the X chromosome, the balance of female determining factors is encoded and male-determining factors on the autosomes are encoded. Thus, females are XX, XXY, and XXYY flies, while males are XY and XO flies. According to this sex-determination principle, if the ratio of X chromosomes to the total number of autosome sets (X/A) is > 1, then that organism would be a super female. The genotype would display an intersex phenotype if the ratio of the X chromosome to the total number of autosome sets (X/A) ranges between 1 and 0.50. For normal females, the X/A ratio is 1.0 and for normal males, 0.5.
Therefore the sex of A, B, C, D will be as follows:-

	Chromosome constitution	Sex-Index
A.	AA + XO	Sterile male
B.	AA + XXX	Super female
C.	AAA + XXY	Intersex
D.	AA + XY	Normal male

So, the correct answer is option A

Note:- Drosophila was one of the first species used for genetic research. Every Drosophila cell determines whether it will be male or female independently of the rest of the organism, resulting in gynandromorphs occurring occasionally, i.e. An organism that incorporates the features of both men and women. In 1910, in a laboratory known as the Fly Room, Thomas Hunt Morgan started using fruit flies in experimental inheritance experiments at Columbia University.