Chapter 22 Bio T1

  1. History
    • Big Bang - 13.7 BYA
    • Solar System began - 4.6 BYA
    • Outer Layers solidify and make oceans - 4 BYA
    • Life emerges 3.5-4 BYA
    • Dinorsaurs 65 Million
  2. 4 Overlapping Stages
    • 1. Nucleotides and AA produced prior to cells 
    • 2. Nuvleotides and AA polymerized (to RNA and DNA)
    • 3. Get into membranes
    • 4. Self Replicate
  3. urey and miller
    know this!
  4. Stage 1 Origin of Organic Molecules
    prebiotic or abiotic synthesis (little - no oxygen)

    • Hypothesis:
    • reducing atmosphere - (urey miller spontaneous creation)
    • extraterrestrial - meteorite brought organic carbon (but would be burned off or damaged)
    • deep sea vent - biologically important formed here between temp gradient between hot and cold
  5. Stage 2 Organic Polymers
    • Prebiotic synthesis of polymers not possible in aqueous solutions (hydrolysis competes with polymerization) 
    • Use clay as enzyme
  6. Stage 3 Formation of boundries
    Probiont (ie lipid layer) - help maintain internal conditions separate from outside
  7. *Characteristic of boundaries of probiont
    1.Keeps outside out and inside in 

    • 2.Polymers inside the protobiont contained
    • information (info carrying molecule)

    3.Allow for chemical reactions inside (ie enzyme function)

  8. living cells evolve from
    • coacervates - droplets form spontaneously, enzymes trapped inside can do primitive metabolic functions 
    • liposomes - Vesicles surrounded by a lipid layer
    • Clay can catalyze formation of liposomes
    • that grow and divide
    • Can enclose RNA
  9. * Stage 4 RNA World: 3 Key RNA functions

    (science favors RNA as first macro molecule of probionts)
    • 1. Ability to store info
    • 2. Capacity for self replication
    • 3. Enzymatic function (ie ribozyme)

    Dna and proteins dont' have all 3 functions! But RNA can!!!
  10. Chemical selection
    chemical w/i mixtures of different chemicals have increased number and have advantage over other chemicals in the mixture

    • ie 
    • 1.One of the RNA molecules mutates and has enzymatic ability to attach nucleotides together (advantage of faster replication)

    • 2.Second mutation produces enzymatic
    • ability to synthesize nucleotides (no reliance on prebiotic synthesis)
  11. tRNa sort of acts like an enzyme so not a stretch to get ribozymes
    grabs amino acide and is very code specific (like lock and key for enzyme)
  12. Bartel and Szostak Demonstrated
    Chemical Selection
  13. Advantages of DNA/RNA/Protein World
    Info Storage - DNA is more stable b/c 2x and complementary so less mutations, so RNA can do something else 

    Metabolism and other cell function - protein have a greater catalytic potential and efficiency (since so diverse). Can also perform other tasks like transport, cytoskeleton, etc).
  14. Fossils
    • Many rocks w/ fossils are sedimentary 
    • older = deeper (relative dating)
  15. Random dates
    • End of permean was mass ext, started mesosoic KT event
    • 65 mya dinosaurs went extinct (meteoroit cause climate change)
  16. radiotope dating
    igneous rock is the best to date bc its molten rock then solidifies
  17. Image Upload 1
    Image Upload 2Image Upload 3
  18. order of time chunks
    Eon, Era, Periods, Epoch

    Kings of lEON went to see vERA wang but she was on her PERIOD, it was EPOCH
  19. Eons
    • Haden
    • Archean
    • Protozoic
    • Phanerozoic 

    bolded is precambrian
  20. 65 mil years ago
    dinosaurs go bye bye
  21. Permian/triasic
    when dinosaurs and mammals appear
  22. first prokaryote
    archean eon
  23. first eukaryotic
  24. order of periods in phanerzoic eon 

    (oldest to youngest)
    come over some day maybe play poker three jacks can take queen
  25. important events in history
    • oldest evidence of a continent 
    • free oxygen in atmosphere
    • first complex organism 
    • first fish 
    • first land plants
    • first dinosaur
    • first mammal 
    • first flowering plant
    • dino go extinct
    • first primate in genus homo
    • first homo sapien
  26. equilibrium can only occur
    • the population is very large
    • mating is random
    • no selection
    • no net change in pool due to mutation 
    • no migration in or out
  27. genetic drift
    smaller population affected more and can get fixed allele faster than larger population
  28. 5 mass extinctions
    • Ordovician
    • Devonian
    • Permian
    • Triassic
    • Cretaceous
  29. human evolution
    • Australopithecus aferensis (lucy)
    • Homo habilis
    • Homo erectus
    • Homo neanderthalesis 
    • Homo sapiens
  30. great apes
    gorillas, bonobos, chimpanzees, orangutan
  31. hominid
    humans + ancestor
  32. taxonomy hierarchy
    • domain 
    • super group (eukaryotes)
    • kingdom 
    • phyla
    • class
    • order
    • family
    • genus
    • species
  33. mutation
    • raw material of mutaiton 
    • if changed on phenotype, environment acts upon that 
    • (silent mutation - same AA but different AA)

    *if negative change then will not be passed down to offspring
  34. Major Environmental Changes
    • Climate Change
    • Atmosphere
    • Land mass
    • Glaciation
    • Flood
    • Volcanic Eruption 
    • Meteoric Impact
  35. stromatolite
    autotrophic cynobacteria
  36. Endosymbiosis Theory
    prokaryote eat prokaryote without digesting it, and they lived happily ever after.
  37. ahcombs razor
    simplest explanation is most likely the right one
Card Set
Chapter 22 Bio T1
bio 112 test 1