Sex determination at birth is decided on the chromosomes the baby has. A female has two X chromosomes, whereas a male has one X and one Y chromosome. According to Medline Plus, in every cell, humans ...

Human biological sex is determined by the sex chromosomes X and Y. In most cases, females possess two X chromosomes, while males have one X and one Y. However, there is some evidence that the Y ...

Most people are born with 46 chromosomes that are divided into 23 pairs. Chromosome pairs carry genes from each parent, which determine a person’s physical characteristics, like their height or eye ...

Genes are segments of DNA (deoxyribonucleic acid) that are located inside every human cell. The DNA inside each cell is tightly coiled in structures called chromosomes. Each chromosome contains a ...

Chromosomes are blocks of DNA (deoxyribonucleic acid). They contain very detailed and specific instructions that determine: How the cells in a baby's body develop. What features the baby will have, ...

In what might be a surprise for some, the male sex chromosome is far more complex than its female counterpart. This is why it’s taken scientists so long to work out exactly what makes a male a male.

The Y chromosome is perhaps the most puzzling part of the human genome. Associated with male development, it is chock-full of repetitive and inverted stretches of DNA, a hurdle that makes it ...

Large blocks of genes conserved through hundreds of millions of years of evolution hint at how the first animal chromosomes came to be. Chromosomes, the bundles of DNA that star in the mitotic ballet ...

Turner syndrome is a chromosomal condition involving a person’s sex chromosomes. It is considered mosaic when an X chromosome is missing in some cells in people who have two X chromosomes. Share on ...

Mosaic trisomy 8 is a rare genetic condition caused by an extra chromosome. Sometimes called trisomy 8 mosaicism, this condition develops well before birth. It's a result of an abnormality in how ...