BIOL10210 Lecture Notes - Lecture 9: Heteroplasmy, Flowering Plant, Gamete
Document Summary
We do want the nucleal dna from the male gamete but we do not want the mitochondrial dna from the male dna. Asymmetry of gametes (and therefore two sexes) evolved to prevent conflict between cytoplasmic genomes. Human sperm cell has less than 100 mitochondria. Heteroplasmy: some organisms get both mitochondria and survive (fungus, angiosperms, bats) How well does dual control work: 70-80% of embryos are aborted in the first weeks of pregnancy, still conflict, has to be a level of compatibility for the lifeform to survive. Failure of two genomes to interact compatibly: full explanation still unknown, but much of the problem may be failed interaction between the two genomes. Two asymmetric sexes = uniparental inheritance of organelles: lesser the conflict at the cellular level. Has to have variation, despite this system that has been astoundingly successful, yet also decrease variation at the cellular level.
