Question 1 : Some bacteria can form resting structures called ___________ that can withstand extremes in temperature, moisture, and radiation.

A. symbionts
B. viroids
C. prions
D. endospores
E. capsids

Question 2  : All but one of the following are false regarding protists. Identify the true statement.

A. Most protists are single-celled organisms; some are multicellular.
B. Protists have cell walls composed mainly of peptidoglycans.
C. All protists are single-celled organisms.
D. Protists are prokaryotic.
E. Protists do not have the ability to move on their own.

Question 3 : What is the main difference between protists and bacteria?

A. Protists cannot cause infections, bacteria can
B. Protists are unicellular, bacteria are multicellular.
C. Protists have a nucleus, bacteria do not
D. Bacteria are always gram-negative, protists are gram-positive
E. Bacteria have DNA, protists do not.

Question 4 : The endosymbiont hypothesis suggests that the mitochondria of eukaryotic cells are descended from captured

A. aerobic bacteria.
B. archaebacteria.
C. eukaryotic algae.
D. cyanobacteria.
E. chemoautotrophic bacteria.

Question 5 : In bacteria, the cell wall is composed mainly of

A. proteins.
B. lipids.
C. peptidoglycans.
D. various polysaccharides.
E. glycoproteins.

Question 6 : Oxygen built up in the atmosphere approximately 2 billion years ago and

A. helped to form the ozone layer that is so important to life today.
B. destroyed ozone forming more oxygen.
C. could not have occurred without the oxygen coming from outer space.
D. occurred due to carbon dioxide being split by lightning strikes.
E. occurred because aerobic organisms required the oxygen.

Question 7 : What term is used to indicate a characteristic that is shared and inherited from a common ancestor?

A. homologous trait
B. outgroups
C. cladistic trait
D. analogous trait
E. derived trait

Question 8 : Of the following, which kingdom contains the most diversity in terms of DNA sequences?

A. Protista
B. Plantae
C. All of these are approximately equivalently diverse.
D. Fungi
E. Animalia

Question 9 : Paleontologists have found fossils dating back 3.6 billion years. These closely resemble

A. fungi.
B. blue-green algae present today.
C. small invertebrate animals.
D. nothing alive today.
E. today's simplest plants.

Question 10 : During which geological era did Pangea break apart?

A. Archean
B. Proterozoic
C. Cenozoic
D. Mesozoic
E. Paleozoic

Question 11 : Prions are composed of

A. DNA.
B. protein.
C. RNA.
D. DNA and protein.
E. DNA, RNA, and protein.

Question 12 : Endospores form

A. during binary fission.
B. when the environmental conditions are favorable.
C. in response to adverse conditions.
D. to produce two offspring from every one parental cell.
E. as a means of genetic recombination.

Question 13 : Kelps are a form of what group of protists?

A. ciliates
B. dinoflagellates
C. slime molds
D. brown algae
E. water molds

Question 14 : Rickettsias belong to which major group of bacteria?

A. cyanobacteria
B. proteobacteria
C. viruses
D. Archaea
E. spirochetes

Question 15 : Most bacteria are

A. photoautotrophs.
B. heterotrophs.
C. chemoautotrophs.
D. symbionts.
E. microbial predators.

Question 16 : Which form of bacterial cells is rod shaped?

A. spirilla
B. bacilli
C. vibrios
D. cocci
E. rhodius

Question 17 : 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 monoxide.
D. consisted of carbon in the form of carbon dioxide.
E. contained nitrogen in the form of ammonia and nitrogen gas.

Question 18 : Eukaryotic cells are thought to have

A. evolved before prokaryotic cells.
B. developed when mitochondria grew much larger in size that they had been previously.
C. first appeared with tough cell walls.
D. appeared about 2.1 billion years ago.
E. first appeared as parts of multicellular organisms.

Question 19 : When taxonomists classify organisms using a phylogenetic approach, they are most concerned with

A. cladists.
B. ingroups.
C. ancestral traits.
D. derived traits.
E. outgroups.

Question 20 : 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 osmotic pressure.
B. be a disadvantage for these organisms and lead to their death and fossil formation.
C. allow the animals to move into different environments easily.
D. protect the animal from predators.
E. make these animals more desirable to predators.