M1 L1: Intro to Genetics Flashcards
How did we know humans had an understanding of genetics?
They knew about domestication and selective breeding to get certain traits in plants/animals
What was Aristotle’s view on genetics? Did it include epigenesis?
Semen has a vital heat that cooks menstrual blood into a fetus. Yes epigenesis
What is epigenesis? Who came up with the idea?
Fetus grows de novo in utero. It does not start as a tiny, fully formed human with proper limbs. William Harvey
What was the Hippocratic School of Medicine theory of genetics? Did it include epigenesis?
Believed humors from male body went into semen. The humors could be diseased or normal, and that influenced the development of the fetus. I don’t think it follows epigenesis?
What’s the Homunculus theory of heredity? Does it include epigenesis?
Semen includes a tiny fully formed human. Grows after implanting. No epigenesis
What’s the Ovist theory of heredity? Does it include epigenesis?
Egg contains fully formed human. Grows when stimulated by semen. No epigenesis
What’s the germ plasm theory? Who came up with it?
Ovaries and testes each have a full set of genetic info, egg and sperm each deliver half to offspring. August Weissman
What’s nuclein? Who proposed it was the genetic material?
Nucleic acid and peoteins. Edmund Beecher Wilson
Who discovered the first genetic disorder? What was it?
Archibald Garrod. Alkaptonuria, black urine disease
What 4 ideas led us to better theories of heredity?
1) Schleiden and Schwann cell theory: all life is made of cells; all cells come from other cells
2) louis pasteur refuted spontaneous generation: living matter can’t arise from nonliving matter
3) refuted fixity of species: species are not fixed; they have changed over time
4) natural selection: 3 premises, 3 conclusions for how species change over time
3 premises of NS
1) species have genetic variation, at least some is heritable
2) some heritable variation affects rates of survival and reproduction
3) species overproduce, produce more offspring than environment can support
3 conclusions of NS
1) there will be a struggle for existence among offspring
2) individuals with traits better fit for the environment will have more survival and reproductive success
3) adaptive traits will accumulate and the population will change through time
What’s blending inheritance? Who believed in it?
Offspring are the average value of the parents. Darwin
What’s the problem with blending inheritance? Who discovered this?
It’s incompatible with NS because advantageous traits will get diluted and never become fixed in populations. Fleeming Jenkin
What does diploid mean?
organism has 2 full sets of genes (maternal and paternal)