Atmospheric chemists think that Earth’s first atmosphere

QUESTION 1

 

Atmospheric chemists think that Earth’s first atmosphere

A.

contained no oxygen atoms.

 

B.

was very similar to today’s atmosphere.

 

C.

consisted of carbon in the form of carbon dioxide.

 

D.

contained nitrogen in the form of ammonia and nitrogen gas.

 

E.

consisted of carbon in the form of carbon monoxide.

 

5 points

QUESTION 2

 

Paleontologists have found fossils dating back 3.6 billion years. These closely resemble

A.

fungi.

B.

today’s simplest plants.

C.

small invertebrate animals.

D.

blue-green algae present today.

E.

nothing alive today.

5 points

QUESTION 3

 

Kelps are a form of what group of protists?

A.

dinoflagellates

B.

slime molds

C.

ciliates

D.

water molds

E.

brown algae

5 points

QUESTION 4

 

Some bacteria can form resting structures called ___________ that can withstand extremes in temperature, moisture, and radiation.

A.

prions

B.

capsids

C.

viroids

D.

endospores

E.

symbionts

5 points

QUESTION 5

 

Oxygen built up in the atmosphere approximately 2 billion years ago and

A.

could not have occurred without the oxygen coming from outer space.

B.

helped to form the ozone layer that is so important to life today.

C.

destroyed ozone forming more oxygen.

D.

occurred because aerobic organisms required the oxygen.

E.

occurred due to carbon dioxide being split by lightning strikes.

5 points

QUESTION 6

 

Of the following, which kingdom contains the most diversity in terms of DNA sequences?

A.

Animalia

B.

All of these are approximately equivalently diverse.

C.

Fungi

D.

Plantae

E.

Protista

5 points

QUESTION 7

 

All but one of the following are false regarding protists. Identify the true statement.

A.

Protists are prokaryotic.

B.

Protists do not have the ability to move on their own.

C.

All protists are single-celled organisms.

D.

Most protists are single-celled organisms; some are multicellular.

E.

Protists have cell walls composed mainly of peptidoglycans.

5 points

QUESTION 8

 

During which geological era did Pangea break apart?

A.

Paleozoic

B.

Archean

C.

Cenozoic

D.

Proterozoic

E.

Mesozoic

5 points

QUESTION 9

 

Eukaryotic cells are thought to have

A.

evolved before prokaryotic cells.

B.

first appeared as parts of multicellular organisms.

C.

first appeared with tough cell walls.

D.

developed when mitochondria grew much larger in size that they had been previously.

E.

appeared about 2.1 billion years ago.

5 points

QUESTION 10

 

When taxonomists classify organisms using a phylogenetic approach, they are most concerned with

A.

ancestral traits.

B.

ingroups.

C.

derived traits.

D.

outgroups.

E.

cladists.

5 points

QUESTION 11

 

What term is used to indicate a characteristic that is shared and inherited from a common ancestor?

A.

derived trait

 

B.

homologous trait

 

C.

outgroups

 

D.

cladistic trait

 

E.

analogous trait

 

5 points

QUESTION 12

 

The endosymbiont hypothesis suggests that the mitochondria of eukaryotic cells are descended from captured

A.

aerobic bacteria.

B.

eukaryotic algae.

C.

archaebacteria.

D.

chemoautotrophic bacteria.

E.

cyanobacteria.

5 points

QUESTION 13

 

Prions are composed of

A.

DNA and protein.

B.

DNA, RNA, and protein.

C.

DNA.

D.

RNA.

E.

protein.

5 points

QUESTION 14

 

Most bacteria are

A.

photoautotrophs.

B.

microbial predators.

C.

symbionts.

D.

chemoautotrophs.

E.

heterotrophs.

5 points

QUESTION 15

 

The Cambrian Explosion provided a wealth of fossil remains for scientists to uncover. Many of the animals from this time period had tough skins or shells. This would

A.

protect the animal from predators.

B.

make these animals more desirable to predators.

C.

be a disadvantage for these organisms and lead to their death and fossil formation.

D.

allow the animals to move into different environments easily.

E.

protect the animal from osmotic pressure.

5 points

QUESTION 16

 

Rickettsias belong to which major group of bacteria?

A.

proteobacteria

B.

cyanobacteria

C.

Archaea

D.

spirochetes

E.

viruses

5 points

QUESTION 17

 

Which form of bacterial cells is rod shaped?

A.

vibrios

B.

bacilli

C.

spirilla

D.

rhodius

E.

cocci

5 points

QUESTION 18

 

What is the main difference between protists and bacteria?

A.

Bacteria have DNA, protists do not.

B.

Bacteria are always gram-negative, protists are gram-positive

C.

Protists cannot cause infections, bacteria can

D.

Protists are unicellular, bacteria are multicellular.

E.

Protists have a nucleus, bacteria do not

5 points

QUESTION 19

 

In bacteria, the cell wall is composed mainly of

A.

glycoproteins.

B.

peptidoglycans.

C.

various polysaccharides.

D.

lipids.

E.

proteins.

5 points

QUESTION 20

 

Endospores form

A.

as a means of genetic recombination.

B.

during binary fission.

C.

when the environmental conditions are favorable.

D.

in response to adverse conditions.

E.

to produce two offspring from every one parental cell