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what was the name Darwin wrote
The origin of species
can individual organisms evolve
no, populations evolve
list post and prezygotic barriers
post: hybrid unviability, hybrid sterility, hybrid breakdown
pre: gametic, mechanical, behavioral, geographic, temporal
describe all major events in earth's history
earth: 4.5 bya
prokaryotes: 3.5 bya
oxygen: 2.7 bya
eukaryotic fossils: 2.1 bya
multicellular eukaryotes: 1.2 bya
colonization of land: 500 mya
humans: 195,000 y
what is parsimony
simpler is better, the explanation that
explains relationships using the fewest evolutionary
events or changes in DNA
how did lamarck think traits were passed down
traits an organism acquires while they are alive are passed down to offpsring
what is genetic drift
when a genetic variation is lost due to random chance
allopatric vs. sympatric and how does polyploidy affect reproductive isolation
allopatric: geographic isolation
sympatric: new species arises in same area.
polyploidy: Arises as the result of total nondisjunction of chromosomes during mitosis or meiosis. creates new species (sympatric)
describe Miller, Urey, Oparin, and Haldane's experiments and hypotheses
Oparin and Haldane: Early Earth conditions favored synthesis of organic compounds. Today’s oxidizing atmosphere NOT conducive to spontaneous synthesis. Early Earth’s atmosphere was likely more reducing
Miller and Urey: Tested Oparin and Haldane’s hypothesis. Recreated environment of early Earth to see if inorganic molecules could form. After 1 week a variety of organic acids formed
(precursors for proteins
why is the fossil record incomplete
no everything is fossilized. some are decomposed.
what is catstrophism
mass extinctions occurred between periods of life
what is microevolution
evolution on a small scale, such as allele frequency change
what is exaptation
Structure that evolved in one context and later was adapted for another function
Ex.: dinosaurs to birds (feathers, lightweight bones)
explain why RNA was the first genetic material.
naturally selected and can act as enzymes (ribozymes)
what do the amount of difference in structures or amino acid sequences indicate about evolution
more differences, the more evolved or further from ancestor. less closely related
how did homologous structures support Darwin's theory
they showed how organisms were related to each other. if they had homologous structures, they most likely shared a common ancestor
give 2 examples of how an organism's phoentype can change due to environment
pH changing flower color
seasonal change in fur color
melanin production in the sun
micro vs. macroevolution
Microevolution: Deals with changes in the gene pool of a single
population
Macroevolution: Includes the origin of new species and higher taxonomic groupings
explain protocells
groups of abiotically produced molecules.
Form spontaneously
Droplets of lipids could form something similar to a phospholipid bilayer (vesicles)
CANNOT reproduce
CAN maintain an internal chemical environment (homeostasis)
Exhibit metabolism & excitability
Natural Selection could refine Protocells containing heredity information
what is the taxonomic order
Kingdom, Phylum, class, order, family, genus, species
what did Miller and urey discover
provided evidence that inorganic components could for organic compounds needed for life under the right conditions
what are the conditions for hardy weinberg equilibrium
large population
no natural selection
no mutations
no gene flow
random mating
ana vs. cladogenesis
ana: transforms one species into another
Cladogenesis: build one NEW specie from a parent, but that parent specie also still exists
explain the conditions and theories of life on early earth
conditions:
1. Abiotic synthesis of small organic molecules
2. Joining small molecule into macromolecules
3. Packaging macromolecules into protocells (droplets with membranes that maintained different internal chemistry from their surroundings)
4. Origin of self-replicating molecules (for inheritance)
theories:
Spontaneous Generation: one theory says that life emerged from inanimate material
Biogenesis: “Life-from-life” principle; cells come from pre-existing cells
explain molecular clocks and both types of dating.
molecular clocks state that genes & genome evolve at constant rates. Relative dating: fossil record, order of existence. absolute dating: radiometric dating, isotopes