lec8 3/8/2012 9:09:00 AM
Reproduction
Why sex?
Human reproduction
o Conception
Early pregnancy loss
Nausea and vomiting during pregnancy NVP
Birthing
o Reproductive health in the modern world
Why sexual reproduction?
Reproduction and sex are different
o Making copies versus jumbling genes
o Sex is not essential for life or reproduction
Budding (eg.plants,bacteria)
Parthenogenesis( aphids,rotifers)
o Other ways to share genetic material, eg. Bacterial
conjugation
Sexual reproduction is costly an hard to explain!
Asexual reproduction is twice as efficient avoids infection
o You produce offspring that are all female and they can
reproduce herself without any imput of any indivudual
o Replicate yourself twice as fast
“two fold cost” of sex ( # progeny +# gene copies)
o do better more copies
what fitness advantage outweighs benefit of asexuality?
What is the point of males?
o Can not reproduce
o Just produces sperm
o Must have other organism to nurture them to become
offspring
Why are there genders?
Sexual reproduction
o Produces only offspring that is 50% related to 1 parent and
50% other parent, not 100 % from mother like in asexual