Women (and all female mammals) have one active X chromosome per cell instead of two. What causes this?
A) modification of the XIST gene so that it is active only on one X chromosome, which then becomes inactive
B) activation of the Barr gene on one of the two X chromosomes that then inactivates
C) crossover between the XIST gene on one X chromosome and a related gene on an autosome
D) inactivation of the XIST gene on the X chromosome derived from the male parent
E) the removal of methyl (CH3) groups from the X chromosome that will remain active
Bacterial colonies, each derived from a single cell Bacterial colonies, each derived from a single c
animal cell
Kitagawa Utamaro, The Fickle Type, from the series Ten Physiognomies of Women.
The Four Steps of The Cell Cycle
A drawing of chromosome I
Chromosome mosaicism