HISTORY OF LIFE

Question 1

Almost zero oxygen ; high methane

Answer 1

Pre-life situation

Question 2

What year did the earliest life forms existed?

Answer 2

3.5 to 3.7 BYA

Question 3

Was formed 2.3 billion years ago

Answer 3

Microbe (Stromatolites)

Question 4

Layered rock; sticky mats of microbes; microbial reefs

Answer 4

Stromatolites

Question 5

How do stromatolites form?

Answer 5

Biofilm

Question 6

Earth’s first photosynthesizers (The Great Oxidation Event)

Answer 6

Cyanobacteria

Question 7

Two well-developed marine stromatolite (blue green algae)

Answer 7

1. Bahamas & Hamelin Pool

2. Western Australia

Question 8

Formation of stromatolite

Answer 8

1. Cyanobacteria form a mat on top of sediment
2. New layer of sediment deposited on top
3. Bacteria grow up through new layer

Question 9

Origin of eukaryotic cells

Answer 9

Endosymbiotic Theory

Question 10

Based on similarities between prokaryotes, mitochondria and chloroplasts. These organelles used to be prokaryotes.

Answer 10

Endosymbiotic Theory

Question 11

Who proposed the endosymbiotic theory? When?

Answer 11

Lynn Margulis 1968

Question 12

Reasons why multicellularity occured

Answer 12

1. Avoid predators
2. Maintain great homeostasis
3. Acquire new specialized cell function
4. Group fitness is augmented over the average fitness of member cells

Question 13

When was multicellularity occured?

Answer 13

~ 1.5 BYA

Question 14

First multicellular organism

Answer 14

Algae

Question 15

What period created all the phyla and 1st predator-prey interaction?

Answer 15

Cambrian

Question 16

Two hypotheses regarding the multicellularity

Answer 16

1. Colonial

2. Syncytial

Question 17

Both protista - from uni to multi - from colony - two radial ancestor - gave rise to 1. Radial 2. Bilateral

Answer 17

Colonial hypothesis

Question 18

Have many nucleids inside but only one cell - cell boundaries - gave rise to 1) Bilateral 2) Radial

Answer 18

Syncytial Hypothesis

Question 19

considered as the first animal and precursor to metazoa

Answer 19

Choanoflagellate protozoan

Question 20

2 MAJOR EONS

Answer 20

Precambrian

Phanerozoic

Question 21

ERA undEr Precambrian Eon

Answer 21

HAP
HADEAN
ARCHEAN
PROTEROZOIC

Question 22

ERA under Phanerozoic EON

Answer 22

PMC
PALEZOIC
MEZOSOIC
ZENOSOIC

Question 23

PERIODS UNDER PALEOZOIC ERA

Answer 23

COSDCP

1. Cambrian
2. Ordivician
3. Silurian
4. Devonian
5. Carboneferous
6. Permian

Question 24

Period under MEZOSOIC

Answer 24

Jurassic
Triassic
Cretacous

Question 25

PERIOD UNDER CENOZOIC

Answer 25

Tertiary

Quarternary

Question 26

can be used to detect the absolute age of any species

Answer 26

Radioactive decay

Question 27

Age of a rock or fossil described in comparison to that of another rock or fossil

Answer 27

Relative Age

Question 28

Actual age of rock or fossil (actual remains) or how long age it formed

Answer 28

Absolute Age

Question 29

Existed for a short length of time; were abundant; inhabited many locations (widespread)

Answer 29

Index fossils

Question 30

How does C-14 form?

Answer 30

1. Cosmic rays bombard the upper atmo
2. Fast moving neurons
3. Neurons collide with atmospheric nitrogen atoms
4. Producing radioactive C14

Question 31

1 half life

Answer 31

5730 yrs old

Question 32

Causes of extinction

Answer 32

1. Cataclysmic events
2. Human interference
3. Evolutionary probs

Question 33

Invasive species

Answer 33

Zebra mussel

Question 34

5 MAJOR EXTINCTIONS

Answer 34

1. Late ordivician
2. Late devonian
3. Permian
4. Jurassic
5. Cretaceous

Question 35

Late ordivician

Answer 35

85%

Severe ice age

Question 36

Late devonian

Answer 36

75%

Anoxic conditions due to algal blooms

Question 37

Permian

Answer 37

95%

Methane eruption, oceans acidified, H25, no coal deposits

Question 38

Jurassic

Answer 38

80%

Volcanism due to Pangea, climate change