Chromosomes and Genes

Mitosis and Cells

All living things are composed of cells. The number of cells within an organism is phenomenal. In every living organism each cell's nucleus contains all of the genetic information needed to replicate the cell. The genetic material within the cell's nucleus takes the form of chromosomes. A chromosome is composed of DNA and contains all of the hereditary information of a cell.

Scientists have discovered that there are two different types of cells within all living organisms, gametes and somatic cells. Somatic cells are body cells. In order to regenerate and make more cells, somatic cells fission in a process called Mitosis, in essence replicating themselves. Gametes are the sex cells within an organism, the common terms are egg and sperm. One gamete contains only half of the chromosomal information from each parent. When united with a corresponding gamete, the genetic material of both combine to form a full set of chromosomes. The new set of chromosomes are used as a "blueprint" for cells to replicate into an organism. To illustrate, the average human cell has 46 chromosomes total, however the gametes contain 23. When the gamete is combined with another gamete, the gamete pair join to form a new cell with 46 chromosomes.

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