History of Life

Question 1

Astrobiologist

Answer 1

A scientist who searches for evidence of life on other worlds.

Question 2

Autotroph

Answer 2

An organism that makes its own food by manufacturing organic compounds such as carbohydrates, that it uses as source of energy and nutrients.

Question 3

Banded iron formation

Answer 3

A sedimentary rock composed of alternating thin layers formed of iron oxide mineals and silica-rich minerals, precipitated from seawater when oxygen, produced by cyanobacteria, reacted with iron dissolved in seawater. Banded iton formations mark the rise of oxygen in the atmosphere.

Question 4

Biogeochemical cycle

Answer 4

A pathway through which a chemical element or molecule moves between the biologic and environmental components of an ecosystem.

Question 5

Biosphere

Answer 5

The sum total of all living organisms and the organic matter they produce.

Question 6

Cambrian explosion

Answer 6

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Question 7

Chemoautotroph

Answer 7

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Question 8

Chemofossil

Answer 8

The chemical remains of organic compounds made by an organism while it was alive.

Question 9

Cyanobacteria

Answer 9

A group of microorganisms that produce oxygen adn carbohydrates by photosynthesis. It is believed that photosynthesis orginated in cyanobacteria.

Question 10

Ecosystem

Answer 10

An organizational unit composed or organisms and geologic components that function in a balanced, interrelated fashion.

Question 11

Evolution

Answer 11

The process by which organisms change through time, driven by the process of natural selection.

Question 12

Evoluationary radiation

Answer 12

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Question 13

Extremophile

Answer 13

A microbe that lives in environments that would kill any other organism.

Question 14

Gene

Answer 14

A large molecule within the cells of every organism encoding all the information that determines what the organism will look like, how it will live and reproduce, and how it differs from all othe organisms.

Question 15

Geobiology

Answer 15

The study of how organisms have influences that been influenced by Earth’s environment.

Question 16

Habitable zone

Answer 16

In the context of astronomy, a habitable zone is the space surrounding a star where water is stable as a liquid. If a planet is within a habitable zone, there is a chance that life could exist there.

Question 17

Heterotroph

Answer 17

An organism that gets its food by feeding directly or indirectly on autotrophs.

Question 18

Metabolism

Answer 18

The process that all organisms use to convert inputs to outputs.

Question 19

Microbial mat

Answer 19

A layered microbial community commonly occurring in tidal flats, hypersaline lagoons, and thermal springs..

Question 20

Microfossil

Answer 20

A fossil that can only be studied microscopically. The oldest microfossils that preserve possible morphologic evidence for life arre tiny threads similar in size and appearnace to modern microbes, encased in chert.

Question 21

Natural selection

Answer 21

The adapation of populations of organisms to new environments. Natural selection is responsible for the development of new species.

Question 22

Photosynthesis

Answer 22

The process by which organisms such as green plants and algae use energy from sunlight to convert water and carbon dioxide to carbohydrates and oxygen.

Question 23

Red bed

Answer 23

A bed of sandstones and shales that is red because of the presence of iron oxide cement that bidns the grains together. The presence of red beds around 2.7-2.1 Ga indicates that oxygen must have been present in the atmosphere to precipitate the iron oxide cements.

Question 24

Respiration

Answer 24

The process that allows an organism to release the energy stored within carbohydrates. All organisms use oxygen to burn, or respire, carbohydrates to creat energy.

Question 25

Stromatolite

Answer 25

A rock with distinctive lamination, believed to have been formed by ancient microbial mats. Stromatolites range in shape from flat sheets to domal structures with complex branching patterns. They are one of th emsot ancient types of fossils on Earth and give us a glimpse of a world once ruled by microorganisms.

Question 26

Correct order of time divisions from largest to smallest

Answer 26

Eon, Epoch, period, era

Question 27

Precambrian era

Answer 27

Makes up 88% of geologic time
Most of earth’s iron core was formed in rocks during this time
Most rocks of this time are devoid of fossils due to the virtual absence of animals and plants
The most common fossils are stromatolites
First multicellular organisms.
First one-celled organisms.
4.5 billion - 540 million years ago

Question 28

Cenozoic era

Answer 28

Age of flowering plants.
Mammals become dominant land animals.
Plate interactions build mountains, cause volcanoes, EQ in Western NA.
"Recent life" era. 
Quaternary + tertiary periods.
"Age of mammals" 
Humans develop.
Extinction of dinosaurs.
Begins 65 million years ago.

Question 29

Paleozoic era

Answer 29

Brachiopods are most abundant fossil.
Era of “ancient life”
By the end, Pangea was formed.
“Age of amphibians”-extinction of trilobites, first reptiles, amphibians abundant.
“Age of fishes”-first insect, fishes dominant, first land plants
“Age of invertebrates”-first fishes, trilobites dominant, first shells
Periods-Devonian, Silurian, Ordovician, Cambrian, Mississippian, Pennsylvanian, Permian

Question 30

Mesozoic era

Answer 30

First flowering plants
First birds
Dinosaurs dominant
"Age of reptiles+dinosaurs" 
Periods-Cretaceous, Jurassic, Triassic
Pangaea broke up
NA plate overrides the Pacific plate
Marsupials and placentals evolve at the end

Question 31

Pleistocene Epoch

Answer 31

Last major ice age

Question 32

Trilobites

Answer 32

Earliest known marine arthropods
Early Cambrian period
Exoskeleton

Question 33

Cephalopods

Answer 33

Mollusk
Body symmetry
Dominant in Ordovician period
Nautiloids

Question 34

Angiosperms

Answer 34

Flowering plant since 140 mya
Seed producing
245 mya

Question 35

Gymnosperm

Answer 35

Seed producing plants
Like trees
Carboniferous period

Question 36

Marsupials

Answer 36

Jurassic