Question

Which of the following statement is true for Barr body?

• A. It is a highly condensed chromosome.
• B. It is an active X chromosome.
• C. It is equivalent to the single Y chromosome of the male.
• D. It is equivalent to the two X chromosomes of the female.

Hint:

Consider the role of X chromosome inactivation in females and its cytological appearance.

Answer 1

The Correct Option is A

The Barr body is the inactivated X chromosome in females, visible as a dense structure within the nucleus. This condensation ensures dosage compensation between males (with one active X chromosome) and females (with two X chromosomes). The inactive X chromosome is highly condensed and transcriptionally silent, contrasting with the active X chromosome.