Sex-linked inheritance 2. Color blindness. (Page 17)
The color blindness is a genetic defect that causes difficulty distinguishing colors. It is a type of inheritance linked to sex, specifically, to the X chromosome. Women have two X chromosomes while men have one X and one Y chromosome. The genes of the X chromosome can be recessive or dominant, and their expression in women and men is not the same because the genes of the X chromosome are The Y chromosome does not pair exactly with the X genes. X-linked recessive genes are expressed in women only if there are two copies of the gene (one on each X chromosome). However, in males there must only be one copy of an X-linked recessive gene for the trait or disorder to be expressed, so they are much more common in males than females. For example, a woman may unknowingly carry a recessive gene on one of her X chromosomes and pass it on to her son, who will express the trait or disorder.
Simulator: Practice simulating color blind crossovers.