📖 what
What is a Barr body?
Human BiologyChromosomes
Quick Answer
A Barr body is an inactivated X chromosome visible as a dense spot in the nucleus. It is found in many cells of females and some other XX individuals.
The Full Story
A Barr body is the condensed, largely inactive form of one X chromosome in cells that undergo X-chromosome inactivation. It appears as a small dark-staining mass in the nucleus. The number of Barr bodies is usually one less than the number of X chromosomes present. It is a classic example of how chromosome biology can differ from the simple chromosome count taught in school.
Key Facts
1.Usually one Barr body forms for each X chromosome beyond the first
2.It is the inactive X chromosome
3.Named after geneticist Murray Barr
YouTube Angle
Suggested video title for this topic:
"The hidden chromosome lump inside the nucleus"