chapter 22

Question 1

What are the preserved remains of the past life ?

Answer 1

Fossils

Question 2

What does the oldest fossil resemble ? How old

Answer 2

Cyanobacteria and 3.5 billion

Question 3

Radiometric dating

Answer 3

a method
of dating samples by
determining the relative
proportions of particular
radioactive isotopes present in
the sample

Question 4

The major environmental changes that could cause extinction

Answer 4

Temperature (Ice Age, tropic vs arctic)
* Composition of atmosphere (O2)
* Shifting of landmasses (continental drift)
* Floods and glaciations
* Volcanic eruptions
* Meteorite impacts

Question 5

When did Prokaryotic cells arise ?

Answer 5

Archaean Eon

Question 6

When was the formation of the earth

Answer 6

500 years ago and earth was too hot

Question 7

When did microbial life flourish in the primordial ocean /

Answer 7

Archean

Question 8

During the archaeon eon all the life forms were..

Answer 8

Prokaryotic and anaerobic

Question 9

Heterotrophs

Answer 9

derive their energy from the chemical bonds within
the organic molecules they consume

Question 10

Autotrophs

Answer 10

directly harness energy
from either light or inorganic molecules

Question 12

What was the first form of life

Answer 12

Unsure

Question 13

What year does multicellular eukaryotes emerge

Answer 13

1.5 billion years ago

Question 13

What was the oldest fossil preserved

Answer 13

Autotrophic Cyanobacteria

Question 14

Cyanobacteria formed in layers is called

Answer 14

Stromatolites

Question 15

When did Eukaryotic cells arise ?

Answer 15

PROTEROZOIC EON

Question 16

Where is it thought of simple multicellular emerged

Answer 16

Aggregation process and by cell divsion and adhesion

Question 16

How does aggregation occur ?

Answer 16

When individual cells find each other and form a colony.
Example: Slime modes

Question 17

What were the first animals

Answer 17

Invertebrates (580-600 mya)

Question 17

When did the phanerozoic eon start ?

Answer 17

543 mya

Question 18

The 3 periods of the Phanerozoic eon

Answer 18

Paleozoic,Mesozoic, Cenozoic

Question 19

Most animals exhibit

Answer 19

bilateral symmetry

Question 20

The paleozoc era covers

Answer 20

300 million years

Question 21

The 6 periods of the Paleozoic era

Answer 21

Cambrian, Ordovician, Silurian, Devonian, Carboniferous,
and Permian

Question 22

What did the Cambrian period cover

Answer 22

(543-490 Mya)
-Rapid incensement in animal diversity

Question 23

Ordovician Period

Answer 23

(490-443 Mya)
- Climate is warmer
- Marine communities evolved
- Early land plants and arthropods have landed ( maybe)
- Large glaciers were formed,

Question 24

Phanerozoic Eon saw the

Answer 24

Diversification
of Invertebrates & Colonization of Land by Plants & Animals

Question 25

Silurian Period

Answer 25

(443-417 mya )
- no major types of invertebrates but changes
- Major colonization of land by terrestrial plants and animals
-Earliest vascular plants arose

Question 26

Devonian Period

Answer 26

(417-354 mya)
- Major increase in the number of terrestrial plant species; ferns, horsetails, and seed plants (gymnosperms) emerge
- Insects emerge
* Tetrapods (amphibians) emerge
* Invertebrates flourished in oceans
* Near the end of the period, a
prolonged series of extinctions
eliminated many marine species

Question 27

Carboniferous Period

Answer 27

• A cooler period where much land was covered by forest
  swamps; coal formed over millions of years from compressed
  layers of rotting vegetation
• first flying insects
• Amniotic egg emerges, which
  was a critical innovation for the
  emergence of reptiles

Question 28

Permian Period

Answer 28

(290-248 mya)
- The largest known mass extinction occurred ( the end )

Question 29

Triassic Period

Answer 29

( 248-206 mya )
- Reptiles were plentiful and new groups arose (crocodiles,
turtles)
* First dinosaurs (a diverse group of reptiles) emerged during the
middle of the Triassic
* First mammals emerged

Question 29

The 3 Mesozoic periods

Answer 29

Triassic. Jurassic and cretaceous

Question 30

Jurassic Period

Answer 30

(206- 144 mya )
Gymnosperms (ex: conifers) continued to be dominant
vegetation; dinosaurs and other reptiles continued to be
dominant land vertebrate

Question 31

Cretaceous Period

Answer 31

(144-65 mya)
-Dinosaurs continued to be dominant land animals

Question 32

The 2 years of the Cenozoic era (65 million years)

Answer 32

Tertiary and Quaternary

Question 33

We are currently in the..

Answer 33

Quaternary Period

Question 33

Tertiary Period (65-1.8 mya) is when

Answer 33

Mammals that survived the Cretaceous began to rapidly
diversify during the early Tertiary
* Angiosperms became dominant land plants;

Question 34

When did Homo sapiens appear ?

Answer 34

200,000 years ago

Question 34

When did hominoids emerge ?

Answer 34

7 mya