Bio Test

What made it possible for O2 to accumulate in the atmosphere and oceans.? (1st hypothesis)

The burial of organic matter destabilizing the photosynthesis-respiration equilibrium

what are the eons in order

Hadean, Archean, Proterozoic, Phanerozoic

When was the Hadean eon

4.6-4 billion years ago

What was the atmosphere made of during the Hadean eon

methane, CO2, and water vapor

During the Hadean Eon, significant cooling caused what?

a rock crust to form

During the Archean Eon, what happens with water?

it condenses to form oceans that cover earth

What introduced fe2 into oceans?

eroded iron and hydrothermal vents

What oxidized the Fe2 into Fe3

the o2 produced by cyanobacteria

What causes banded patterns on ocean floors

fe3 percipitation on the ocean floor

When did the first life forms develop

during the Archean Eon

What where the first life forms?

simple anaerobic prokaryotes

Cyanobacteria evolved during the end of which eon?

Archean Eon

What are Cyanobacteria?

prokaryotic cells that are able to undergo photosynthesis

why are Cyanobacteria important?

they started producing oxygen

when oxygen was first created, what did it react with?

iron in the oceans

When does Oxygen begins accumulating in the atmosphere

during Proterozoic Eon

the first eukaryotic cells evolve when?

during Proterozoic Eon

When does Boring Billion occur during this time

proterozoic eon

What is the same during the boring billion

Photosynthesis and respiration

What lead to o2 increase after the boring billion

dynamic continental changes, burrying organic matter

What evolve near the end of the proterozoic eron

Very simple plants and animals

What marks the beginning of the Phanerozoic Eon?

the Cambrian explosion

What happens with oxygen during the Phanerozoic Eon?

it fluctuates and rises to 36%,

What are the 5 mass extinctions of the phanerozoic Eon in order?

Ordovician, Devonian, Permian, Triassic, Cretaceous

What are mass extinctions?

Period of time where over 75% of species go extinct

How long do mass extinctions take to occur?

thousands to millions of years

What caused the Ordovician extinction and what happened?

The ice age - extinction of marine animals

What caused the Devonian extinction and what happened?

Oxygen depletion - loss of fishes

What caused the Permian extinction and what happened?

Volcanic eruption - 96 of animal species become extinct

What caused the Triassic extinction and what happened?

Volcanism - almost all animals become extinct, dinosaurs dominated

What caused the cretaceous extinction and what happened?

Asteroid - extinction of dinosaurs

What made it possible for O2 to accumulate in the atmosphere and oceans.? (2nd hypothesis)

the depletion of reduced compounds (fe2)