Sex determination
What Sex determination means in Biology GCSE, as defined for AQA, OCR.
Definitions of Sex determination
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Reference: AQA
Sex is determined at fertilisation by the sperm: an X-bearing sperm gives a female and a Y-bearing sperm gives a male.
Whether an individual develops as female or male is determined by one pair of chromosomes, the sex chromosomes.
Biological sex in humans is determined by the sex chromosomes, with XX in females and XY in males.
The 23rd pair determines sex: females (XX) have a homologous pair, but males (XY) do not.
Topics that use Sex determination
- Sex determination (AQA GCSE)
- Inheritance (OCR GCSE)
Related terms
- Asexual reproduction
- Autosomes and sex chromosomes
- carrier identification
- chromosomes
- continuous variation
- data interpretation
- Diploid and haploid
- direct proportion
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