Chapter 4 Study guide

____ is a process by which organisms with characteristics suited to the environment will survive and reproduce.

Artificial selection

The end of the Paleozoic Era was signaled by ____.

mass extinction of land and sea animals

t/f: Charles Darwin proposed the theory of natural selectio

true

t/f: The Mesozoic Era means the era of middle life.

true

If a species can adapt to a changing environment, or ____, its descendants will survive.

evolve

t/f: The exoskeleton of a trilobite consists of four lobes or sections.

false

Plate tectonics may affect organic evolution because movement of plates may cause a change in ____.

the enviroment

t/f: When Pangaea separated it broke into two large land masses known as Eurasia and Australioland.

false

Periods are divides into groups known as as _______________.

epochs

t/f:Precambrian time contained 3 eons, the Hadean, the Archean, and the Proterozoic

true

The division of Earth’s history into smaller units makes up the ____.

geologic time scale

t/f: The Cenozoic Era means era of recent life.

true

t/f: The Cenozoic Era is divided into three periods.

false

t/f:The Alps and Andes formed during the Cenozoic Era.

true

____ on the geologic time scale are marked by major, striking, and worldwide changes in the type of fossils present.

eras

The Alps, Andes, and Himalaya formed in the ____.

Cenozoic Era

t/f: Cyanobacterai are blue-green algae thought to be one of the earliest forms of life on Earth.

true

This supercontinent formed at the end of the ____________________ Era.

Paleozoic

t/f: The Palezoic Era means the era of recent life.

false

Reptiles evolved from an ancestor of amphibians that developed a(n) ____.

egg with a strong outer shell that kept it from drying out

Trilobites are considered to be _______________ because they lived in vast regions of the world during specific periods of geologic time.

index fossils

Life-forms that existed during the Paleozoic Era included ____.

all of the above a. fish b. trilobites c. reptiles

The ____ formed during the Paleozoic Era.

Appalachian Mountains

____________________ was the supercontinent shown in Figure 14-

Pangaea

The change in a species over time is known as _______________.

organic evolution

Scientists believe dinosaurs evolved from ____ during the Mesozoic Era.

reptiles

Today, some scientists think that ____.

birds evolved from dinosaurs

t/f: Birds first appeared during the Jurassic Period.

true

t/f: The Himalaya moutains formed when Australia collided with India.

false

A life-form in the Precambrian time was ____

cyanobacteria

Little is known about much of Earth’s early history because ____

all of the above

Animal life in the Cenozoic Era includes ____.

all of the above

Dinosaurs are thought to have been protective of their young because ____.

they might have been warm-blooded

t/f: The present day period is the Quaternary Period and it began about 1.8 million years ago.

true

t/f: The super continent Panaea formed at the beginning of the Paleozoic Era.

False

____ existed during the Mesozoic Era.

both a and c

The development of ____ factored in the development of complex organisms.

all of the above ozone b. oxygen c. cyanobacteria

Eons are divided into groups known as _______________

eras

t/f: Angiosperms are flowering plants that produce seeds with no outer covering.

false

Changes in the environment result in ____.

physical changes in species

The hard scales of reptiles’ skin helped them to retain water, enabling them to adapt to the ____ climate during the Mesozoic Era.

dryer

Humans first appeared during the ____ Era.

Cenozoic

A life-form that evolved during the ____ Era was the dinosaur.

Mesozoic

The longest subdivision in geologic time is a(n) ____.

eon

t/f: The Appalachain Mountains were formed during the Paleozoic Era.

true

t/f: The Tertiary Period started 65 million years ago and continues through today.

false

Eras are divided into groups known as _______________.

periods

Cenozoic Era life-forms include ____.

all of the above humans reptiles marine mammals

A(n) ____________________ is a group of organisms that only reproduces with other members of their group.

species

Only epochs in the ____ Era(s) have been given specific names.

Cenozoic

t/f: Gymnosperms are plants that produce seeds but not flowers.

True

Changes in the trilobite exoskeleton can be attributed to ____.

both a and b

t/f: The end of the Paleozoic Era was marked by the extinction of 90% of all marine life and 70% of all land species.

true

The longest subdivision of geologic time is are _______________.

eons

Mammals first appeared in the ____________________ Period.

Triassic

Animal life in the Paleozoic Era included all of the following EXCEPT ____.

humans

Homo sapiens probably appeared ____ ago.

400,000 years

Angiosperms are the dominant land plant today because they developed ____.

hard seed coats

Pangaea separated into ____.

two large landmasses

t/f:Mammals first appeared during the Ordivician Period.

false

The division of Earth’s history makes up the ________________.

geologic time scale

The change in environments that may have occurred at the end of the Paleozoic Era may have been caused by ____.

plate tectonics

t/f: Homo sapiens were thought to first appear about 140,000 years ago.

true

Which trilobite characteristic did not change through time?

3-lobed body

Trilobites are index fossils because they ____.

all listed a. changed slowly through time b. lived over large areas of the world c. exhibit specific characteristics

The Mesozoic Era ended about 65 million years ago.

True

Geologic time is divided into units based upon types of ____.

organisms