Sex Determination (AQA GCSE Biology)
Revision Note
Written by: Lára Marie McIvor
Reviewed by: Lucy Kirkham
Did this video help you?
Human Chromosomes
Ordinary human body cells contain 23 pairs of chromosomes
22 pairs control characteristics only, but one of the pairs carries the genes that determine sex
In females, the sex chromosomes are the same (XX)
In males, the sex chromosomes are different (XY)
Sperm cells determine the sex of offspring
Determining Sex
The inheritance of sex can be shown using a genetic diagram (known as a Punnett square), with the X and Y chromosomes taking the place of the alleles usually written in the boxes
Punnett square showing the inheritance of sex
Last updated:
You've read 0 of your 5 free revision notes this week
Sign up now. It’s free!
Did this page help you?
