Sex chromosomes are chromosomes, or packages of DNA, that are found inside the nucleus of all of your cells. There are two different kinds: X and Y, which determine whether you’re biologically male ...

Sex is determined in a variety of different ways throughout the animal kingdom. In mammals, it is determined genetically, not by temperature, as it can be in reptiles. Typically, females have two X ...

Chromosomes are thread-like structures located inside the nucleus of animal and plant cells. Each chromosome is made of protein and a single molecule of deoxyribonucleic acid (DNA). Passed from ...

Women are born with two X chromosomes and inherit one from each parent. But in every cell of their body, just one X chromosome is needed – so the other is randomly inactivated. Some cells use only a ...