BIO 182 Chapter 22

The geological time scale is subdivided into which of the following eons?

• Proterozoic

• Phanerozoic

• Archaean

• Hadean

The timeline of Earth is divided into four eons. These occurred in the following order: the Hadean eon, the _ eon, the _ eon, and the Phanerozoic eon.

Archaean; Proterozoic

The first three eons in the geological time scale are known as the _ because they preceded the _ period.

Precambrian; Cambrian

In which two domains of life does horizontal gene transfer still play a major role in fostering evolutionary change?

• Bacteria

• Archaea

The emergence of organisms capable of performing photosynthesis added which of the following chemicals to the Earth's atmosphere?

Oxygen

The _ timescale is a time line of the Earth's history and major events from its origin approximately 4.55 _ years ago to the present.

geological; billion

Which of the following types of organisms flourished during the Archaean Eon?

Microbial life

Place the eons of the geological timescale in the correct order from earliest (at the top of the list) to the most recent (at the bottom of the list).

1. hadean

2. archaean

3. proterozoic

4. Phanerozoic

An important factor that was extremely influential in the emergence of prokaryotes and eventually eukaryotes was the availability of _ required to survive and reproduce.

energy

In the geological time scale, the first three eons are called the:

Precambrian era

The _ composition of the atmospheric gases surrounding the Earth has changed over the past 4 billion years.

chemical

Which of the following organisms can absorb light energy and use it via photosynthesis to synthesize organic molecules?

Autotrophs

Many scientists believe the first forms of life on Earth were ______ because it would have been simpler for them to use the organic molecules in the prebiotic soup as a source of energy.

heterotrophs

During the _ Eon, diverse microbial life flourished in the primordial ocean.

Archaean

Which of the following consequences resulted from the emergence and proliferation of cyanobacteria?

• Ability to produce organic molecules from CO2 prevented the depletion of organic foodstuffs.

• Ability to produce oxygen led to an increase in the level of O2 in the atmosphere.

Which of the following factors greatly influenced the appearance of new species of prokaryotes and subsequently eukaryotes?

Energy

When did eukaryotic cells arise?

During the Proterozoic eon

Plant cells contain DNA in three organelles: the nucleus, the _, and the _.

mitochondria; chloroplasts

Match the type of organism with the strategy used to obtain energy.

autotroph → directly harnesses energy from either inorganic molecules or light

heterotroph → derives energy from the chemical bonds within the organic molecules consumed

An endosymbiotic relationship between bacteria and archaea could explain the:

origin of eukaryotic cells

If autotrophs were the first forms of life on Earth, what could they have used as an energy source?

• Chemicals near the deep-sea vents

• Light energy from the sun

Levels of oxygen gas increased as a result of the emergence and proliferation of ______, which were some of the earliest photosynthetic organisms.

cyanobacteria

A relationship in which a smaller organism lives inside a larger organism is called a(n) ______ relationship.

endosymbiotic

Eukaryotic cells arose during the _ Eon, which began 2.5 billion years ago and ended 543 _ years ago.

Proterozoic; million

The first multicellular eukaryotes are thought to have emerged in the middle of the _ Eon.

Proterozoic

Which of the following eukaryotic organelles contain DNA?

• Nucleus

• Mitochondria

• Chloroplasts

The most popular current explanation of the origin of eukaryotic cells involves the process of ______, in which a smaller cell is maintained as an organelle within the larger cell.

endosymbiosis

Dinosaurs appeared and disappeared during the _ era of the Phanerozoic eon.

Mesozoic

Phanerozoic means "well-displayed life", referring to the abundance of fossils of _ and _ that have been identified from this eon.

plants; animals

An endosymbiotic relationship is one in which a small organism

lives inside of a larger organism.

Place the three eras of the Phanerozoic eon in the correct order from oldest at the top to most recent at the bottom.

1. paleozoic

2. mesozoic

3. cenozoic

When did the first multicellular eukaryotes arise?

During the Proterozoic eon

Match up the period of the Paleozoic era with the major events that happened during that time.

Cambrian → diversity of animal species increased rapidly

Silurian → large terrestrial colonization by plants and animals

Devonian → seed plants and tetrapods first appeared

Carboniferous → reptiles first appeared

Match the era of the Phanerozoic eon to the events that occurred during the era.

Paleozoic → plants and animals moved onto land

Mesozoic → dinosaurs appeared and disappeared

Cenozoic → mammals were the largest land animals

The period of the Paleozoic era that came before the Silurian and after the Cambrian is

Ordovician

The Phanerozoic Eon is subdivided into which of the following eras?

• Cenozoic

• Mesozoic

• Paleozoic

The _ explosion resulted in a large increase in animal groups, including all the existing major types of invertebrates, plus many others that no longer exist.

Cambrian

The Phanerozoic eon is composed of the Paleozoic, Mesozoic, and _ eras

Cenozoic

Trilobites and brachiopods are examples of hard-shelled marine invertebrates that first appear in the fossil record during the ______ period.

Ordovician

During the Silurian period, terrestrial plants developed what adaptation that prevented them from drying out?

Cuticle

The period of the Paleozoic era in which seed plants, tetrapods, and insects first appear is the _ period.

Devonian

Put the periods of the Paleozoic era in order from oldest at the top of the list to most recent at the bottom of the list.

1. cambrian

2. ordovician

3. silurian

4. devoninan

5. carboniferous

6. permian

Many of the existing major types of marine invertebrates arose during the _ period.

Cambrian

Insects first appeared during which period?

Devonian

The Ordovician period is noted for its diversity of ______, such as trilobites and brachiopods.

marine invertebrates

In the Carboniferous Period large deposits of coal were created from the abundance of what?

Dead vegetation

Which of the following events occurred during the Silurian period?

• The ancestral relatives of spiders and centipedes became prevalent.

• Vascular plants made their appearance.

• Terrestrial plants evolved adaptations to prevent them from drying out.

Which of the following groups first emerged during the Mesozoic era?

• mammals

• dinosaurs

• angiosperms

Which of the following are periods in the Cenozoic era?

• Tertiary

• Quaternary

Which of the following types of vegetation formed during the Devonian period?

• ferns

• trees

• gymnosperms

_ are mainly tree-dwelling species evolved for small, arboreal insect-eating mammals about 85 mya.

Primates

During the ______ period, much of the land was covered by forested swamps, and rich coal deposits were found in rocks.

Carboniferous

Grasping hands, large brains, digits with flat nails, binocular vision, and complex social behavior are defining characteristics of mammals called _.

primates

Mass extinctions occurred at the end of which two periods in the Mesozoic era?

• Triassic

• Cretaceous

Which of the following primates have opposable thumbs and big toes?

• Chimpanzees

• Gorillas

• Gibbons

Which of the following is also known as the Age of Dinosaurs?

Mesozoic era

Which of the following animals have large brains compared to their body size?

• Gorillas

• Orangutans

• Humans

The period of the Cenozoic era in which we live in now is called the _ period.

Quaternary

The _ are the group of mammals that care for their offspring for a relatively long time.

primates

Primates evolved from a group of small, arboreal, insect-eating mammals about how many years ago?

85 million

The defining characteristics of primates are:

• large brains

• binocular vision

• grasping hands

• nails instead of claws

• complex social behavior

• well-developed parental care

Relatively large brains are found in which of the following?

• Whales

• Humans

Opposable thumbs and opposable big toes are characteristic of all primates.

False

Primate _ are fairly large for their body sizes and they are well-developed.

brains

Which of the following animals have a tendency for complex social behavior and care for their young for a relatively long time?

• Chimpanzees

• Humans

• Apes

Taxonomists classify primates into two categories: _ and _.

strepsirrhini; haplorrhini

Which of the following primates are classified as strepsirrhini?

• Lemurs

• Bush babies

• Pottos

Which of the following animals displays grasping hands?

Raccoons

Which of the following primates are classified as haplorrhini?

• Chimpanzees

• Orangutans

• Gorillas

Primates can be divided into two broad groups. What are they?

• Haplorrhini

• Strepsirrhini

Compared to monkeys, hominoids have ______ shoulder joints, and a ______ spine.

more mobile; shorter

The strepsirrhini display which of the following characteristics?

• Eyes positioned more toward the side of the head

• Wet noses

Hominoids are split into the:

• greater apes

• lesser apes

Orangutans, gorillas, chimpanzees, and humans are examples of hominoids called the _ apes.

greater

Which of the following are features of haplorrhini?

• Fully forward-facing eyes

• Dry noses

Which of the following shapes would best describe the trend of human evolution from a common ancestor to modern humans?

A tree, with each branch representing a species over time

Most hominoids have which of the following characteristics?

• Broader rib cages than monkeys

• More mobile shoulder joints than monkeys

Who discovered the skeletal remains of the Australopithecus named "Lucy"?

Donald Johanson

The twenty species of _ are split into two groups: the lesser and greater apes.

hominoids

Which of the following is a lesser ape?

Gibbon

Which scenario best describes the trend of human evolution?

Several species coexisting at the same point in time

Which of the following species of hominins were also known as handy man?

Homo habilis

The earliest fossils of Australopithecus were discovered in which area?

South Africa

Homo habilis and Paranthropus lived ~2 million years ago in which area?

East Africa

Which of the following human habits helped propel the evolution of an increased brain size?

Meat-eating habit of early man

Homo ergaster arose approximately how many years ago?

2 million years ago

_ was also known as handy man because stone tools were found with the fossil remains.

Homo habilis

Although it is still controversial, it is thought that Homo _ gave rise to Homo ergaster.

habilis

Identify the hominin that was probably the first to leave Africa.

H. ergaster

Which of the following characteristics provide evidence that Homo habilis was a meat eater?

• Smaller teeth than other hominins

• Much smaller jaws than other hominins

The human brain uses a substantial amount of the body's energy to function. What percent of the total body's energy is used by the brain?

20

Which species is derived from the Latin meaning wise man?

H. sapiens

Which of the following characterizes Homo ergaster?

• Human-looking face and skull

• Used hand axes

There is some evidence to suggest that Homo habilis likely gave rise directly to:

Homo ergaster

According to the multiregional model of the origin of H. sapiens, H. sapiens evolved from which of the following species?

H. ergaster

It is thought that gestation of the hominin _ _ was shortened as a the result of larger head size of the child and narrower pelvis of the female.

Homo ergaster

DNA analysis of the remains of Neanderthals and Denisovans indicate that they interbred with _ _.

Homo sapiens

Compare the brain capacity of Homo sapiens and Neanderthals.

Homo sapiens' brain capacity is slightly smaller than Neanderthals.

If the temperature decreases for a relatively long time, mammals with (thick or thin) _ fur will have a greater survival rate.

thick

Which model of the origin of Homo sapiens is is more widely accepted?

The out-of-Africa model