Population genetics

### Episode 6: Population Genetics - Evolution at the Gene Level Welcome to the sixth episode of our course on Evolution and Natural Selection! Having explored Darwin's ideas and the concept of natural selection acting on individuals, we now shift focus to **Population Genetics**. This field merges Darwinian evolution with Mendelian genetics to study how genetic variation changes within entire populations over time. This episode defines key concepts like population, gene pool, allele frequency, and genotype frequency. We'll discuss the sources of the genetic variation essential for evolution (mutation and recombination) and introduce the crucial Hardy-Weinberg equilibrium principle as a baseline for detecting evolutionary change in populations.

Check your understanding

These are the same multiple-choice questions you will see in the Quiz section after you listen to the episode. Use them here to preview or review the answers.

What is the primary focus of study in population genetics?

  1. The structure and function of individual genes.
  2. The development of individual organisms from embryo to adult.
  3. Genetic variation within and among populations and how it changes over time.
  4. The evolutionary history and relationships between different species (phylogenetics).
  5. The process of protein synthesis within a cell.

What term describes the total collection of genes and their alleles within a population?

  1. Genome
  2. Genotype
  3. Gene pool
  4. Phenotype
  5. Karyotype

In a population of 100 diploid individuals, the frequency of allele 'A' (p) is 0.7. What is the frequency of allele 'a' (q)?

  1. 0.7
  2. 0.49
  3. 0.3
  4. 0.09
  5. Cannot be determined

What is the ultimate source of all new alleles in a gene pool?

  1. Genetic recombination
  2. Natural selection
  3. Mutation
  4. Gene flow
  5. Random mating

Which of the following conditions are required for a population to be in Hardy-Weinberg equilibrium?

  1. Mutations must occur frequently.
  2. Mating must be random.
  3. Natural selection must favor specific genotypes.
  4. The population must be small.
  5. No gene flow (migration) occurs.
  6. No natural selection occurs.

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