BSCI106 exam 3

  1. irreducible complexity
    idea that evolution is not true because there is no such thing as an eye without all of its parts for example.
  2. extaptation
    • adaption evolved for a different use
    • ex: human leg from lizards, antennae, trans-membrane channels
    • NOTE: ADH- allowed digestion of alcohol then became lens of eye
  3. Hardy-Weinberg Equilibrium
    • evolution is not occuring because
    • 1- mutation isn't occuring
    • 2- natural selection isn't occuring
    • 3- infinitely large population
    • 4- all members of the population breed
    • 5- all mating is totaly random
    • 6- everyone has same number of offspring
    • 7- no migration/immigration
  4. HWE equation
    • pchart?chf=bg,s,00000000&cht=tx&chl=p%5E2%20%2B2pq%2Bq%5E2&chs=202x36=1
    • p= frequency of dominant allele
    • q=frequency of recessive allele
    • chart?chf=bg,s,00000000&cht=tx&chl=p%5E2%2Cq%5E2&chs=80x36= frequency of dominant, recessive genotype
  5. evolution
    change in an allele frequency in a population over time
  6. mutation
    • change to DNA base pairs/ change in genetic material not caused by recombination
    • - humans have 100-200 new ones
    • - most are corrected by error checking enzymes
    • - most significant mutations happen in regulatory parts of genes
    • - random
  7. Neutral Mutation
    • no affect on fitness
    • - non synonymous mutations are also neutral
    • - good before but useless now
  8. Columbus Connection?
    -looking for spices
  9. genetic drift
    • random chance change of allele frequencies
    • - population bottleneck
    • - sampling error ( sometimes individuals reproduce due to chance)
    • - coincidence, natural disaster
    • - damaged fitness
  10. gene flow
    migration of individuals and gamete dispersal
  11. fixation/fixed allele
    allele is the only variant that exists in the population for that gene
  12. mutation rates
    • the rate at which mutations occur over time
    • measured in changes per base pair
  13. founder effects
    • - Pennsylvania Amish population
    • - small population with low genetic diversity colonizes a new area in isolation
    • - results in a very low genetic diversity of the new population
    • -uncommon disorders become common
  14. lethal equivalents
    when two carriers of recessive disorders reproduce and produce offspring with that disorder
  15. Why so much variation?
    • - mutation
    • - trade offs of same /different traits
    • - hidden recessives that are passed on without being expressed
  16. Trade-offs
    • benefit comes at a cost, finds a balance between two
    • - brca gene increases fertility but with a higher risk of cancer
  17. diseases?
    • - dominant are hard to get out
    • - recesive not a huge worry
    • - any dominant disease- only needs one dom. allele
  18. sickle cell example/ signifigance
    • SS- fine
    • Ss- carrier (small amount of disease/ resistant to malaria)
    • ss- diseased

    example of heterozygote advantage
  19. Equilibrium
    different allele conditions in different conditions balance out via selection
  20. spatial variation
    subpopulations in different areas, fragmented from whole population will have different fitness values
  21. temporal variation
    seasons have different fitness influences
  22. frequency dependent selection
    only genotypes alone in population
  23. allele fitness?
    based on rarity
  24. self-incompatibility
    self fertilization is not possible, promotes intercourse and diversity
  25. why not more evolution?
    • not as much variation
    • gene flow
    • physical laws
    • evolution only works with what exists, nothing new
  26. whip tailed lizard example
    • all female population that clones
    • once had males because of coital impersonating
  27. Another way of thing about HWE?
    punnet square of whole gene pool
  28. example of HWE factor in real life?
    coral reefs do mate almost randomly
  29. when is there no selection pressure against a variant?
    • little impact on fitness
    • temporal/spatial variation
    • old age
    • somatic mutations
  30. somatic mutations
    • mutations only in body cells that do not get passed down to offspring
    • Ex: barry bonds steroid abuse
  31. germ-line mutations
    do get passed down
  32. frequency of new genotype in population
  33. frequency of new allele in population
  34. Why doesn't selection go further?
    • trade-offs- too much armor slows you down
    • ancestry- strange solutions stay if they are good enough to increase relative fitness
  35. goal of selection
    • grandbabies!
    • not long term gain of species
  36. conserved gene/change/phenotype and why?
    • does not change based on selection because:
    • 1) too risky (testicles)
    • 2)not inherently bad so no need to change
    • Ex: testicular structure because 4 legs were actually meant to protect it
  37. biggest influence on drift
    population size
  38. allele frequencies
    change in individual populations (evolution) but alleles themselves are fixed or lost in different populations
  39. mutation-drift balance
    rate of mutations/rate lost
Card Set
BSCI106 exam 3
exam 3 terms, concepts