9477 / 2027

Chapter 16 / 5 short lessons

Population genetics

Count allele copies, use Hardy-Weinberg with confidence, and explain why variation persists.

H2 Biology / 9477 / 2027 syllabus

What do you think?

An allele is recessive. Must it be rare?

Lessons

0 of 5 marked as read
01

Count alleles, not just organisms

Calculate allele frequencies directly from diploid genotype counts.

About 5 min
About 5 min
02

Build the Hardy-Weinberg model

Connect random gamete combinations to p squared, 2pq and q squared.

About 6 min
About 6 min
03

Work backwards from a recessive phenotype

Infer allele, genotype and phenotype frequencies from suitable equilibrium data.

About 6 min
About 6 min
04

Know when the model applies

Explain equilibrium assumptions and interpret departures without overclaiming.

About 6 min
About 6 min
05

Why harmful alleles can persist

Explain how recessive masking and balancing selection preserve genetic variation.

About 6 min
About 6 min
What you will be able to do
  • Separate allele, genotype and phenotype frequencies.
  • Use and evaluate the Hardy-Weinberg model.
  • Explain how harmful recessive alleles can remain in populations.

Ready to try it without your notes?

Start with a quick check or explain a biological result in your own words.

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