Quiz 17: Viruses, Bacteria, and Protists

How are the algae traditionally categorized? A) by the mode of motility B) by their method of sexual reproduction C) by the the color of their pigment D) by the type of habitat in which they are found E) by their mode of feeding

Which species are representatives of the green algae? A) diatoms, Volvox, and Spirogyra B) coralline algae, Volvox, and Spirogyra C) Chlamydomonas, Volvox, and Spirogyra D) Chlamydomonas, Volvox, and coralline E) diatoms, Chlamydomonas, and Volvox

Which of the following provides support for the endosymbiotic hypothesis? A) Double membranes are around mitochondria and chloroplasts. B) Mitochondria and chloroplasts have their own genomes. C) Mitochondria and chloroplasts can synthesize proteins. D) Mitochondria and chloroplasts contain genes that are strikingly similar to bacterial genes. E) All of the above statements provide support for the endosymbiotic hypothesis.

Which of the following is a characteristic only found in some viruses? A) an inner core of nucleic acid B) a protein capsid C) is an obligate intracellular parasite D) an envelope E) genomes consisting of either DNA or RNA

A virus is specific to a particular type of host cell because A) only certain hosts enter the environment inhabited by the virus. B) not every virus contains metabolic machinery which can replace that of the host cell. C) a glycoprotein onthe viralcapsidis a specific match to a receptor on the surface of a compatible host cell. D) a host cell must be malfunctioning, or a virus cannot infect it. E) the genome of the virus must be similar to that of its potential host.

Which is the correct order of events in the lytic cycle of a bacteriophage? A) attachment - penetration - biosynthesis - maturation - release B) integration - penetration - biosynthesis - maturation - release C) attachment - integration - biosynthesis - maturation - release D) attachment - biosynthesis - maturation - release E) penetration - attachment - biosynthesis - release - maturation

A researcher infects a bacterium with a bacteriophage and notices that the infection does not immediately bring about the destruction of the host cell. Instead, the phage's genetic material is copied whenever the host reproduces. Which viral replication cycle is described here? A) integration cycle B) lysogenic cycle C) biosynthetic cycle D) lytic cycle E) emergence cycle

Citrus tristeza virus (CTV) damages and kills susceptible citrus trees around the world. It can be spread by grafting of infected plants, and by aphids, insects with piercing mouthparts that they use to suck fluid from plants. Which of the following would be ineffective in controlling the spread of CTV? A) use of insecticides to control the aphids B) destruction of infected plants C) production of transgenic citrus lines using genes from resistant plants D) quarantine of fields with infected plants E) application of antibiotic drugs to citrus plants

Animal viruses that have an envelope enter cells by A) injecting their nucleic acid into the cell's cytoplasm. B) fusing with the plasma membrane. C) endocytosis. D) plasmolysis. E) either fusing with the plasma membrane or endocytosis.

Retroviruses A) contain DNA. B) contain the enzyme reverse transcriptase. C) produce RNA from DNA. D) only invade plants. E) produce protein directly from DNA.

Which of the following is an emerging virus? A) HIV B) H5N1 C) West Nile D) SARS E) All of the above are considered emerging viruses.

Your task as a researcher is to develop a new drug to prevent retrovirus infections in newly exposed individuals. Which of the means listed is likely to be the most effective? A) blocking enzyme action B) destroying the viral genome C) dissolving the capsid D) preventing conjugation E) disrupting the viral envelope

Viroids and prions are alike in that both are infectious A) cell types. B) proteins. C) molecules. D) DNA. E) RNA.

Why don't new biological macromolecules form abiotically from nonliving matter on the Earth today? A) The special environmental conditions that are required do not exist. B) There are not enough of the various elements needed. C) There is not enough available energy. D) There is no need for biological macromolecules. E) Biological macromolecules do arise abioticallybut are quickly consumed by organisms.

Cell-like structures that may have resulted from macromolecular self-assembly are referred to as A) prokaryotes. B) protocells. C) protoypes. D) archaea. E) protists.

What would you most likely call a long chain of bacterial cells that are spherical in shape? A) Streptococcus B) Staphylococcus C) Streptobacillus D) Diplococcus E) Streptospirillum

A bacteria's genetic material can include A) a circular chromosome. B) plasmids. C) latent bacteriophage DNA. D) a circular chromosome plus plasmids. E) a circular chromosome, plasmids, and latent bacteriophage DNA.

Which means of genetic recombination in bacteria is facilitated by use of a pilus? A) transformation B) transduction C) conjugation D) both transformation and transduction E) translocation

Which of the following statements regarding bacterial endospores is false? A) Endospores can survive in extremely harsh environments. B) Within an endospore is a copy of the bacterial chromosome. C) An endospore contains a small amount of cytoplasm material. D) Endospores can survive for very long periods of time. E) Endospores are reproductive structures.

In the infamous anthrax attacks of 2001, several letters were received at the offices of two U.S. senators and various news media outlets. The letters contained dry granular or powdery material. Seventeen people who came into contact with the material from the letters suffered anthrax infections; five more died of anthrax. How could dried-out material cause anthrax? A) Anthrax bacteria are acellular infectious particles. When they came into contact with living hosts, they entered the hosts' cells, took over their metabolic machinery, and caused them to produce more bacteria. B) Anthrax bacteria can form endospores under harsh environmental conditions. The material in the letters contained endospores of anthrax bacteria, which germinated and grew in the more favorable environment of the victims' bodies. C) Anthrax bacteria can form endospores in order to reproduce. A few active bacteria in the letters started to produce enormous numbers of endospores upon contact with the anthrax victims. D) Anthrax endospores are highly motile by flagella. When the endospores came into contact with human hosts, they swarmed into the bodies of their victims. E) None of the choices are correct.

Cyanobacteria are important producers, more specifically called A) photoautotrophs. B) saprotrophs. C) chemoautotrophs. D) saproautotrophs. E) photoheterotrophs.

Bacteria that secrete digestive enzymes into their surroundings in order to decompose nonliving organic matter are called A) chemoautotrophs. B) symbiotes. C) saprotrophs. D) parasites. E) photoautotrophs.

Without bacteria in the environment, A) adequate amounts of carbon would not be available to living organisms. B) plants would not be able to grow due to lack of nitrogen. C) bioremediation would have limited use as a tool to clean up pollutants. D) there would be a shortage of decomposer organisms. E) All of the choices are correct.

You take a large sample of soil and divide it among individual pots. You then separate the pots into two groups. In the first group, every pot of soil has been sterilized. In the second group, none of the pots of soil have been sterilized. You plant soybean seeds in all the pots. What would you expect to see as the seeds sprout and grow? A) The plants growing in the sterile soil are bigger because they have not been exposed to any bacteria. B) The plants growing in the non-sterile soil are bigger because they have mutualistic associations with nitrogen-fixing bacteria. C) The plants growing in the sterile soil are bigger because they do not have to compete with nitrogen-fixing bacteria in order to obtain usable nitrogen. D) The plants growing in the non-sterile soil are bigger because saprotrophic bacteria produce nutrients for them. E) There is no difference in size between the plants growing in the sterile soil and those in the non-sterile soil.

Some species of pathogenic bacteria are able to attack specific cells in the human body due to structures called A) adhesion factors. B) bioremediaton factors. C) flagella. D) conjugation pili. E) cilia.

What evidence supports the idea that archaea are more closely related to eukaryotesthan to bacteria? A) Archaea and eukaryotes initiate transcription in the same fashion. B) Archaea and eukaryotes both have cell walls with peptidoglycan. C) Archaea and eukaryotes share some ribosomal proteins and have similar types of tRNA. D) Archaea and eukaryotes initiate transcription in the same fashion, share some ribosomal proteins, and have similar types of tRNA. E) None of the choices supporta close relationship between eukaryotes and archaea.

Penicillin is an antibiotic drug that interferes with peptidoglycan synthesis in bacteria, eventually resulting in cell death. What effect would you predict if you applied penicillin to archaea? A) The archaea would die due to the weakening of their cell walls. B) The archaea would not be affected, since they do not contain peptidoglycan. C) The archaea would not be affected, since none of the archaea have cell walls. D) The archaea would die due to their inability to synthesize protein for their cell walls. E) None of the choices are correct.

Archaea A) have plasma membranes but lack cell walls. B) have plasma membranes, and most have cell walls. C) lack plasma membranes, but most have cell walls. D) have neither plasma membranes nor cell walls. E) have double plasma membranes and no cell walls.

In which type of environment would you be most likely to find methanogenic archaea? A) hot, acidic B) high salt concentration C) anaerobic D) aerobic E) dry

Which type ofarchaea use a pigment related to the rhodopsin, a pigment found in human eyes, to absorb solar energy and pump chloride ions? A) methanogens B) halophiles C) thermoacidophiles D) alkaliphiles E) psychrophiles

Which of the following applies to algae but not protozoans? A) chemoheterotrophs B) have a means of locomotion C) are eukaryotes D) were previously classified as animals E) photosynthetic

All of the following are true statements about algae except A) algae are eukaryotes. B) algae are photoautotrophs. C) algae are producers. D) algae were once classified as plants. E) most algae have some form of locomotion.

One group of protozoans which are nonmotile, produce spores, and have disease-causing species is the A) foraminiferans. B) trypanosomes. C) sporozoans. D) amoeboids. E) radiolarians.

As a result of drinking contaminated water, a patient contracts amoebic dysentery. Would an antibiotic drug that inhibits peptidoglycan synthesis be beneficial in treating the amoeba infection? A) Yes, because it would weaken the cell walls of the amoebas and cause them to die. B) No, because amoeba are not bacteria and do not have peptidoglycan. C) Yes, because antibiotics are always beneficial in treating infectious diseases. D) No, because the cell walls of the amoeba that causes dysentery contain calcium carbonate, not peptidoglycan. E) Yes, because the amoeba would not be able to reproduce.

Which statement about slime molds is incorrect? A) Slime molds are eukaryotic. B) Slime molds are classified in supergroup Ameobozoa. C) Slime molds produce spores. D) Slime molds are chemoheterotrophs. E) Slime molds are most commonly found in coastal areas.

The _____of a virus is enclosed by a _____capsid. A) nucleic acid; protein B) membrane; protein C) nucleic acid; membrane D) protein; nucleic acid E) RNA; DNA

Naked strands of RNA not covered by a capsid are A) viroids. B) archaea. C) prions. D) retroviruses. E) viruses.

A viroid is a naked, infectious _____molecule. A) protein B) DNA C) RNA D) fatty acid E) enzyme

Which of these is mismatched? A) malaria - protozoan B) AIDS - virus C) kuru - prion D) tetanus - bacterium E) food poisoning - archaea

Which statement about bacteria is incorrect? A) All bacteria are pathogenic to humans. B) Bacteria are prokaryotes. C) Most bacteria are chemoheterotrophs. D) Bacterial cells reproduce by binary fission. E) A bacterial cell has one chromosome.

Which of these is mismatched? A) cilia - bacteria B) flagella - bacteria C) pseudopods - slime molds D) flagella - Euglena E) pseudopods - amoebas

Protists can be A) unicellular only. B) unicellular or colonial, but not multicellular. C) colonial only. D) colonial or multicellular, but not unicellular. E) unicellular, colonial, or multicellular.

Which of these is mismatched? A) Paramecium - ciliate B) Chlamydomonas - green alga C) Plasmodium - sporozoan D) Giardia - zooflagellate E) Salmonella - amoeba

African sleeping sickness is caused by a A) trypanosome. B) sporozoan. C) prion. D) bacterium. E) virus.

Which of the following groups contains the foraminifera? A) stramenopiles B) apicomplexans C) dinoflagellates D) rhizaria E) ameobozoa

Which of the following are acellular? A) prions B) protozoans C) archaea D) algae E) bacteria

Which of the following groups contains at least some members that have cell walls? A) protists only B) bacteria only C) archaea only D) protists, bacteria and archaea E) None of the members of the above groups have cell walls.

Which sporozoan characteristic is most consistent with a parasitic lifestyle? A) lack of motility B) chemoheterotrophism C) unicellular D) lack of light-absorbing pigment E) eukaryotic

Which of the following is not a characteristic of Paramecium? A) a macronucleus produces mRNA and directs metabolic functions B) motile with cilia C) a micronucleus functions in reproduction D) engulfs prey with pseudopods E) chemoheterotrophic

Which of the following is unique to the lysogenic cycle? A) attachment B) penetration C) integration D) biosynthesis E) maturation

Which group of organisms are viroids(not viruses)most likely to parasitize? A) plants B) bacteria C) fish D) fungi E) cattle

What is the main structural difference between a virus and a viroid? A) Viroids do not have a capsid covering. B) Viruses do not have a capsid covering. C) Viroids contain DNA, while viruses do not. D) Viruses contain RNA, while viroids do not. E) There is no structural difference between the two.

Which of the following structures would enable a plant virus to move from one plant cell to the next? A) plasmodesmata B) vesicles C) vacuoles D) gap junctions E) recognition proteins

What feature enables the paramecium to move? A) cilia B) contractile vacuole C) flagella D) nucleus E) pseudopodia

Which group of algae are associated with red tide? A) red algae B) green algae C) brown algae D) diatoms E) dinoflagellates