Meiosis is when the original number of chromosomes in a cell get cut in HALF. This half (a gamete) joins with another to form a whole. Males use meiosis to make sperm cells. Females use meiosis to make egg cells. There is 23 chromosomes in sperm cells. There are 23 chromosomes in egg cells. If the egg and the sperm unite then you will get a baby with 46 chromosomes.

Mitosis: when a single-celled organism doubles all of its chromosomes and divides, making two identical "daughter cells".