Based on Lyon’s hypothesis, what will be the number of Barr bodies found in a human female suffering from Down’s syndrome
$0$
$1$
$2$
$3$
A man who carries a sex linked gene on his $Y$ chromosome will transmit this gene to
When a cross is made between offspring and its parents, it is known as
Which of the following diseases results from the genetic inability to synthesize a single enzyme?
Chiasmata firstly seen in
When a cluster of genes shows linkage behaviour they