Biology 123 Ch 25

Front 1

conditions that made life possible

Back 1

abiotic synthesis of small organic molecules (amino acids and nitrogenous bases)

which turned into macromolecules such as proteins and nucleic acids

the formation of protocells (droplets with membranes that maintained an internal chemistry)

the origin of self replicating molecules

Front 2

atmosphere compounds similar to early earth

volcanoes

alkaline vents

Back 2

formed amino acids

Front 3

harold urey and stanley miler

Back 3

tested oparin and haldane's hypotheses that earth's early atmosphere was a reducing environment where organic compounds formed

Front 4

vesicles

Back 4

may be precursor to life

spontaneous formation (lipids to water)

lipid bilayer

can "reproduce" on its own

Front 5

RNA

Back 5

first genetic material

probably inside vesicles, passed on to daughter cells which natural selection could then act on

= formation of protocells

Front 6

fossil record

Back 6

found mostly in sedimentary rocks in strata

biased for long existing, abundant, hard parts, widespread species

Front 7

geological record

Back 7

standard time scale

Front 8

four eons

Back 8

Hadean - origin of earth

Archaean - oldest prokaryotes

Proterozoic - oldest eukaryotes

Phanerozoic - last half billion years, time most animals have existed

Front 9

three eras of phanerozoic eon

Back 9

Paleozoic

Mesozoic

Cenozoic

Front 10

stromatolites

Back 10

earliest direct evidence of life

layered rocks that form when certain prokaryotes bind thin films of sediment

Front 11

mesozoic periods

Back 11

Triassic - origin of mammals, gymnosperms (cone bearing plants)

Jurassic - dinosaurs abundant and diverse, gymnosperms dominant plants

Cretaceous - flowering plants, many organisms become extinct at end

Front 12

key paleozoic periods

Back 12

cambrian - sudden increase in diversity of animal phyla

devonian - bony fish, first tetrapods and insects

carboniferous - origin of reptiles

Front 13

first eukaryotes

Back 13

nuclear envelope, mitochondria, endoplasmic reticulum, mitochondria, cytoskeleton

endozymbiont theory - mitochondria and plastids were formerly prokaryotes that began living in larger cells

Front 14

plate tectonics

Back 14

earth's crust is composed of plates on earth's surface

Front 15

adaptive radiation

Back 15

periods of evolutionary change with many new species

follows mass extinctions, evolution of new novel characteristics, the colonization of new reasons

Front 16

heterochrony

Back 16

evolutionary change in the rate or timing of development

Front 17

paedomorphosis

Back 17

sexual maturity during childhood