eco and evo 4

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eco and evo 4
2015-09-30 01:08:50

exam 1
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  1. what is an example of homologies?
    vertebrate limbs
  2. homoplasies
    • bird and bat wings, thylacine and timber wolf, nubian vulture and turkey vulture
    • panda's thumb
  3. how to determine if it is homologous?
    • same fundamental structure
    • same relations to surrounding bones
    • same embryonic development
  4. what is the difference between ancestral and derived homologies?
    • one is present in common ancestor and one evolved after
    • the distinction is called character polarity
  5. what is the common ancestor of whales?
  6. cladogram
    diagram used in cladistics to show relations among organisms
  7. phylogram
    the evolutionary history of a group of organism, length of branch indicates amount of evolution
  8. what are three main statistical technique
    • unrooted tree
    • principal of parsimony 
    • principle of max likelihood
  9. principle of max likelihood
    the most likely phylogeny is the one that has the highest probability of having produced the observed sequences
  10. what is population genetics
    study of patterns of genetic variation
  11. if population is fixed for an allele, what does it mean
    when population exhibits only one allele at a particular gene
  12. allele frequency
    • relative frequency at a particular locus
    • fraction 
    • it is the fraction of all chromosomes in the population that carry that allele
  13. what is evolution
    change in allele or genotype frequency over time.
  14. what is balancing selection
    acts to maintain two or more alleles in a population
  15. does genetic drift lead to adaptation why?
    the alleles whose frequencies are changing are not affecting an individuals ability to survive or reproduce
  16. what does adaptive radiation result from?
    • diversity of resources
    • natural selection accelerates the rate of speciation and adaptation
  17. how can speciation occur without natural selection?
    by genetic drift
  18. paraphyletic
    includes some but not all descendants of common ancestor
  19. what its the closest relatives of four legged land vertebrates
  20. characteristics of tiktaalik
    fins, gills, scales (fish), but skull was flat,functional neck and ribs
  21. synamorphy
    shared by two or more taxa and present in most recent ancestor
  22. eusthenopteron
    first bits of our upper arm and leg
  23. first true finger and toes, lacked wrist
    amphibian acanthostega
  24. ichthyostega
    flat skull (amphibian, beginning to walk on land), transitional between fish and tetrapods
  25. when are genetic switches that make fingers, arm bones and toes do their thing?
    during 3-8th week after conception
  26. what is zone of polarizing activity
    • patch of tissue that causes pinky side to be diff from thumb side
    • when removed or injected with vitamin A creates mirror image of duplication
  27. what genes in flies make one body segment look different from another?
    • hedgehog gene
    • sonic hedgehog gene (chicken)
  28. what is the difference in teeth in carnivores vs. plant eaters
    • carnivores have blade like molars (cut meat)
    • plant eaters: flatter teeth (macerate leaves)
  29. what is the mineral that makes enamel hard?
  30. what is different about us and reptile teeth?
    reptiles change teeth all the time
  31. where is tritheledont found and what is it?
    • nova scotia
    • between mammal and reptile 
    • starts to show teeth in front is different from back
  32. what are actually conodonts
    • most common fossil between 500-250 MYA
    • teeth of ancient jawless fish (no hard bones)
  33. lampreys
    very primitive fish with no jaws, made living by attaching to other fish and feeding on their bodily fluids
  34. first animal with bony heads
    • ostracoderms
    • head, covered by teeth
  35. simplest cranial nerve
    attach to one muscle or organ
  36. cranial nerve
    nerves that supply the muscles
  37. trigeminal nerve
    control muscles and carry sensory info from our face to our brain
  38. otx gene
    active in front where first gill arch forms
  39. amphioxus
    • dichotomy between vertebrates (notochord and nerve cord) and invertebrates (worm)
    • closest relatives to animals with heads (worms with gill slits)
    • 530 million years ago
  40. when does blastocyst attach to uterus so embryo can join bloodstreams
    6th day
  41. what are the features of tube within a tube arrangement shared by
    all animals with backbone four weeks after conception
  42. major difference between human and shark
    humans' first arch forms some ear bones, we do not see in sharks
  43. important patch of tissue containing all info for cell to develop was
    • the organizer
    • noggin was another example
  44. until what month is the earth dominated by single cell microbes
  45. where was the most primitive versions of our body plans from?
    sea anemone
  46. teeth, cartilage, bone which is hardest
    teeth, bone then cartilage
  47. martin boraas
    single cell alga, introduced predator, then alga evoked to form 8 cells
  48. what is the closest microbe relatives of animals with bodies like sponge and placozoans?
  49. what constitutes tree bodies
    have molecular rivets (hold them together) and cell communication tools
  50. what is the most common protein in animals
  51. after how much time are we tube within a tube and have three germ layers
    fourth week after conception
  52. how many sets of hox genes does humans have
  53. which part of ear is most ancient and sends nerve impulses to our brain?
  54. what are we humans trading smell for?
  55. what have whales and dolphins traded olfactory genes for?
    breathing ones
  56. most primitive fish alive on planet today (jawless, single nostril), have both air and water smelling genes
    lampreys and hagfish
  57. how much does light sensing cells make up in the sensory genes
  58. what is opsin used for?
    convey info from outside to inside of cell
  59. camera like eye is common to what
    every creature with a skull
  60. how can we see rich colors?
    we have more color receptor
  61. how did our eye color increase congruent with evolution
    diversification of forests 55 million years ago
  62. Aniridiae
    miss large pieces of their eyes
  63. pax6
    eyeless gene in mouse