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Biology-Related Homework Help Genetics and Developmental Biology Topic started by: loljaneysaur on Jun 10, 2014



Title: Which of the following are properties of a Barr body?
Post by: loljaneysaur on Jun 10, 2014
Which of the following are properties of a Barr body? It can be more than two answers.

A. The number of Barr bodies per cell is always equal to half the number of X chromosomes present.
B. It is formed as part of a mechanism for dose compensation.
C. It is the same X chromosome in every cell.
D. It is an inactivated X chromosome.
E. It is a darkly stained region near the nuclear envelope of interphase cells.

Thanks! lol


Title: Re: Which of the following are properties of a Barr body?
Post by: skip5284 on Jun 10, 2014
A Barr body is the inactivated X chromosome that is usually found in the nuclei of female somatic cells.

It can also occur in males when there is an abnormality and the male is XXY instead of the normal XY, a condition known as Klinefelter's syndrome. In this case, the male somatic cells would also contain a Barr body.

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The Barr body is the highly-condensed chromatin structure taken up by an inctivated X chromosome. The number of Barr bodies equal the number of inactive chromosomes.


Title: Re: Which of the following are properties of a Barr body?
Post by: megan.barkley on Mar 2, 2015
Correct answers:
B. It is formed as part of a mechanism for dose compensation.
D. It is an inactivated X chromosome.
E. It is a darkly stained region near the nuclear envelope of interphase cells