NEETZoologyPrinciples of Inheritance and Variation
What does the XY type of sex determination involve?
Options
- AMales and females have different numbers of chromosomes
- BMales have a Y-chromosome that is larger than the X-chromosome
- CFemales have two Y-chromosomes, and males have none
- DMales have one X and one Y chromosome, while females have two X chromosomes
Correct answer
D. Males have one X and one Y chromosome, while females have two X chromosomes
Step-by-step solution
These observations led to the investigation of a number of species to understand the mechanism of sex determination. In a number of other insects and mammals including man, XY type of sex determination is seen where both male and female have the same number of chromosomes. Among the males an X-chromosome is present but its counterpart is distinctly smaller and called the Y-chromosome. Females, however, have a pair of X chromosomes. Both males and females bear the same number of autosomes. Hence, the males have auto