genetic variation and meiosis

• two main events during meiosis that lead to genetic variation:

  • crossing over of chromatids
  • independent segregation of chromosomes
• crossing over of chromatids in meiosis I means each of the four daughter cells formed from meiosis contains chromatids with different alleles
• independent segregation of chromosomes leads to genetic variation due to the shuffling of chromosomes
• 1. each homologous pair of chromosomes has one chromosome from your dad and one from your mum
• 2. when homologous pairs are separated (meiosis I), it's completely random which chromosome from the pair ends up in which cell
• 3. the four daughter cells from meiosis have completely different combinations of those maternal and paternal chromosomes
• 4. this is called independent segregation
• 5. the 'shuffling' of chromosomes lead to genetic variation in any potential offspring