TED-ED: Secrets of the X chromosome - Robin Ball

The video explains how identical twins can have different traits due to genetic differences, focusing on color blindness. It describes how genetic information is stored in chromosomes, with a special focus on the X and Y chromosomes that determine biological sex. The process of X inactivation, which occurs in individuals with two X chromosomes, is detailed, explaining how it can lead to differences in traits like color blindness. The video also discusses how mutations in X chromosome genes can lead to disorders, and how these are often less severe in individuals with two X chromosomes due to the randomness of X inactivation.

What is the Barr body and what role does it play in X inactivation?

Discuss the implications of mutations in X chromosome genes.

How does the presence of two X chromosomes affect the expression of certain traits?