Cell Division-Meiosis B5

(notes taken from the CGP revision guides)

• Gametes have half the usual number of chromosomes.
• During sexual reproduction, an egg and a sperm combine to form a new cell, called a zygote.
• All human body cells have two copies of the 23 chromosomes. But gametes only have one copy of each chromosome.
• So when the egg and the sperm combine the zygote will contain 46 chromosomes - one set of 23 from each parent.
• Gametes are produced by Meiosis.
• Meiosis involves two divisions. It produces new cells that only have half the original number of…