"All but one of this lungfish's 19 chromosomes is the size of the entire human genome, so it takes a lot of energy to copy that DNA. And the nucleus and cell that encase it must be bigger." ...

The nucleus of each human body cell contains 46 chromosomes. Each chromosome contains about 1000 genes. There is enough DNA in all the cells in a human body to stretch to the sun and back again ...

In fact, the gene may one day disappear altogether. "The early 'proto-Y' chromosome was originally the same size as the X chromosome and contained all the same genes," Kent and Ellis said.

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 ...