Question

You begin your investigation by examining the chromosomes of the two athletes with a karyotype analysis (a procedure that isolates an entire set of chromosomes when they are condensed for mitosis). the results are shown below, along with control samples from a normal female and a normal male.

Answer 1

The barr bodies will be present in only female control, and absent in all the rest. While SRY gene will be absent in only the female control and present in all rest.

Explanation:

The Barr bodies are the dark bodies that are seen inside the nucleus of WBCs in females. These are actually the condensed X chromosomes which is seen in females as they have 2 X chromosomes and one of them remain silent and is seen as Barr bodies.

The SRY gene is actually the TDF gene or Testis Determining factor which secretes a protein called the Sex determining Region Y protein. Its present in the Y chromosome of males and one of the very few functional genes of Y chromosome.

In the given Karyotype of the 2 athletes, we can see that both the athletes are males as they are having one X chromosome and one Y chromosome. So they are males. And hence, both of them will be having the SRY gene and in both of them, Bare bodies will be absent.