Each human cell contains 23 pairs of chromosomes that carry DNA within their nucleus. The X and Y chromosomes, commonly referred to as the sex chromosomes, are one such pair. They determine the ...

Down syndrome is a genetic disorder caused by an extra chromosome 21, affecting brain and body development. It leads to ...

The reason is that when cells divide in preparation to make sperm and egg, all 23 chromosome pairs line up to exchange random bits and pieces of DNA with their matching partner before separating.

It is a genetic condition caused when an unusual cell division result in an extra full or even partial copy of chromosome 21.

In truth, biological sex, like a lot of scientific categories, is nuanced. It's defined by multiple criteria – including chromosomal, chemical and physical factors – that can, and do, change over a ...

The number of chromosomes varies between species. In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46. Twenty-two of these pairs, called autosomes, look the same in both ...

Each cell with a nucleus contains chromosomes, which are made from DNA Human body cells each contain 23 pairs of chromosomes, half of which are from each parent. So, human gametes (eggs and sperm ...

Each human body cell contains 46 chromosomes. These can be arranged into 23 pairs. Each chromosome in a pair carries the same types of genes. The 23rd pair are the sex chromosomes: In females ...

The Principle of Independent Assortment describes how different genes independently separate from one another when reproductive cells develop. Independent assortment of genes and their ...

I gave birth to a beautiful baby girl with almond shaped eyes,” a woman named Sarah wrote on Cincinnati Children’s Hospital’s website. “The doctors and nurses didn’t notice, but I did. After days of ...

Students and staff at Sierra House Elementary School in South Lake Tahoe will be recognizing World Down Syndrome Day on ...

In particular, it explains that humans have one fewer chromosome pair in their cells than apes, due to a mutation found in chromosome number 2 that caused two chromosomes to fuse into one.