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Barr body

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What is BARR BODY? What does BARR BODY mean? BARR BODY meaning, definition & explanation

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Stable chromosomal association of MSL2 defines a dosage-compensated nuclear compartment

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Cheek Epithelial Cells: How to Prepare a Wet Mount Microscope Slide

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Chromatin domains and the interchromatin compartment form structurally defined and functionally int

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2.3.3 Identify structures from electron micrographs of liver cells

A Barr body is the inactive X chromosome in a female somatic cell, rendered inactive in a process called lyonization, in those species in which sex is determined by the presence of the Y or W chromosome rather than the diploidy of the X. The Lyon hypothesis states that in cells with multiple X chromosomes, all but one are inactivated during mammalian embryogenesis. This happens early in embryonic development at random in mammals, except in marsupials and in some extra-embryonic tissues of some placental mammals, in which the father's X chromosome is always deactivated.
  • Mechanism