Sex determination. in Drosophila is determined by the ratio of

Question

Sex determination. in Drosophila is determined by the ratio of (A) number of X-chromosomes and sets of autosomes (B) sets of X-chromosomes and number of autosomes (C) number of X-chromosomes and number of autosomes (D) X-and Y-chromosomes.

Tardigrade Admin · Accepted Answer

Sex in Drosophila melanogaster is determined by genie balance theory proposed by Calvin Bridges (1926). According to this theory, instead of XY chromosomes, sex is determined by the ratio between X-chromosomes and autosome genomes in Drosophila. Bridges found that genic ratio (X/ A) of 1.0 produces fertile females, whether the flies have XX + 2A or XXX + 3A chromosome complement. A genie .ratio XI A of 0.5 forms a male fruit fly, This occurs in XY + 2A as well as XO+ 2A. Hence, the expression of maleness is not controlled by Y-chromosome, but is instead localized on autosomes.

Q. Sex determination. in Drosophila is determined by the ratio of

number of X-chromosomes and sets of autosomes

sets of X-chromosomes and number of autosomes

number of X-chromosomes and number of autosomes

X-and Y-chromosomes.