BIOL108 Lecture Notes - Lecture 2: Corm, Anglerfish, Proterozoic

• School: University of Alberta
• Department: Biology (Biological Sciences)
• Course: BIOL108
• Professor: Richard Moses

Document Summary

Hypothesis for evolution of diploidy and meiosis: dna replication error gave rise to diploidy or fusion of two haploid cells. Adv of diploidy: more genetic variation, protect from changing environment. Dis adv of diploidy: cross over (minimised by keeping like chromosomes close so that if they (cid:272)ross o(cid:448)er it (cid:449)o(cid:374)"t (cid:271)e a pro(cid:271)le(cid:373): meiosis protects from crossover errors. Asexual- cloning, more offspring, passing on a100% of the genes. Sexual: fewer kids, not passing all the genes. Variation in sex roles: penis duels in hermaphroditic flatworms, male female devotes energy towards producing gametes. In hermaphroditic animals, they are both male and female: corm and jack-in-the-pulpit, plants decide if they want to be male or female, plant reserves food in the corm, based on reserves in corm they change gender. Very small, one leaf and no flower: cuttlefish pretend to be male or female. Mimics female: anglerfish: video: how does a male gets screwed.