Populations

• Species

  • A group of similar organisms that an breed to produce fertile offspring
  • The exist as one or more populations
• Population - spec definition

  • A group of organisms of the same species occupying a particular space at a particular time that can potentially interbreed
• Gene pool

  • The range of alleles for all the genes for a population at one time
• Allele frequency

  • The proportion of each allele within within a population
  • Usally a percentage
• The Hardy–Weinberg principle provides a mathematical model, which predicts that allele frequencies will not change from generation to generation.
• 5 assumptions made by Hardy-Weinberg principle

  • Random mating
  • Very large population size
  • No mutations/ change to DNA base sequence
  • No gene flow/ genetic
  • No natural selection
• p

  • Dominant allele
• q

  • Recessive allele
• p2

  • Frequency of homozygous dominant
• 2pq


  Frequency of heterozygous
• q2

  • Frequency of homozygous recessive
• Hardy-Weinberg principle equation

  • p2 +2pq + q2 =1
  • p + q = 1