Exam 2 iClickers Flashcards
(29 cards)
- Why are viruses considered acellular?
A. They do not have a nucleus
B. They do not have a phospholipid-based membrane C. The cannot replicate independently
D. They do not have genetic material
C. The cannot replicate independently
- The plaque assay for counting viruses will measure:
A. Only infectious viral particles
B. All viruses, including infectious and non-infectious particles
C. Approximately 10% of all viruses present
D. The number of infected host cells
A. Only infectious viral particles
- What is the fundamental premise of the regressive hypothesis for the origin of viruses?
A. Viruses evolved at the same time as their host cells
B. Host cells gained the ability to replicate semi-autonomously and transmit their nucleic acid
genomes
C. Viruses were once independent cells that became dependent on host cells
D. None of these choices
C. Viruses were once independent cells that became dependent on host cells
- Which of the following is not a question concerning viral evolution?
A. What is the origin of viruses?
B. How old are viruses?
C. Do viruses affect cellular evolution?
D. Are viruses monophyletic?
C. Do viruses affect cellular evolution?
- What is the fundamental premise of the progressive hypothesis for the origin of viruses?
A. Viruses evolved at the same time as their host cells
B. Hosts gained the ability to replicate semi-autonomously and transmit their nucleic acid
genomes
C. Viruses were once independent cells that became dependent on host cells
D. None of these choices
B. Hosts gained the ability to replicate semi-autonomously and transmit their nucleic acid
genomes
- Which of the following is not a strength of the primordial genes hypothesis?
A. The existence of RdRps
B. An ancient lineage that infects all three domains of life
C. The existence of reverse transcriptase
D. Present day viruses are intracellular parasites
D. Present day viruses are intracellular parasites
- What is the viral shunt?
A. Increasing the DOM and POM by cell lysis
B. Virus infected cells will sink to the seafloor at a faster rate than uninfected cells
C. Mode of transport for viruses in the ocean
D. Viruses will lyse cells and make nutrients available for bacteria
A. Increasing the DOM and POM by cell lysis
D. Viruses will lyse cells and make nutrients available for bacteria
- Which of the following is not an environmental factor that affects virus dynamics?
A. Pollution
B. Virus morphology
C. Salinity
D. UV radiation
B. Virus morphology
- Which of the following species interactions does not benefit both organisms?
A. Mutualism
B. Synergismc
C. Commensalism
D. Amensalism
C. Commensalism
D. Amensalism
- Which of the following is not a negative interaction?
A. Competition
B. Parasitism
C. Commensalism
D. Antagonism
C. Commensalism
- If a mutualistic organism acquired virulence factors, it would be recognized as a:
A. Mutualist
B. Commensal
C. Parasite
D. Ectosymbiont
C. Parasite
- If one species produces folate that is necessary for another organisms growth, this interaction would be considered as:
A. Predation
B. Parasitism
C. Syntrophism
D. Commensalism
C. Syntrophism
D. Commensalism
- Which of the following is not a mechanism that PGPR utilize to control pathogens?
A. Lytic enzymes
B. Siderophore production
C. Antibiotic production
D. Phytohormone production
D. Phytohormone production
- Once rhizobia enter the plant cell through the infection thread, they undergo rapid multiplication and differentiation into nitrogen-fixing cells called:
A. Elementarybodies
B. Nitromorphs
C. Bacteroids
D. Shizonts
C. Bacteroids
- If you want to find the area in soil that harbors the largest number of bacteria, where should you look?
A. In the surface layer because there is a high concentration of organic material there
B. Immediately adjacent to roots because released root material is rich in amino acids and organic acids that support microbial growth
C. In non-plant associated soil because there is less competition with plants for nutrients
D. In deep soil layers because important microbial nutrients tend to diffuse down through the soil
column
B. Immediately adjacent to roots because released root material is rich in amino acids and organic acids that support microbial growth
- What is the oxygen-binding protein found in plant root nodules?
A. Cytochrome c B. Flavoprotein C. Leghemoglobin D. Hemoglobin E. Siderophore
C. Leghemoglobin
- The fact that some secondary symbionts are also found free-living would suggest:
A. They do not have an obligate symbiotic relationship with their hosts
B. The symbiotic relationship with the host is likely relatively new
C. Both of these choices
D. Neither of these choices
C. Both of these choices
- The hydrogen and carbon dioxide produced in the gut of the termite are used to produce ______ by symbiotic microbes.
A. Methane
B. Lactate
C. Acetate
D. Glucose
A. Methane
C. Acetate
- Which of the following is NOT a feature of a primary symbiont?
A. They have reduced genomes
B. They can be found in bacteriocytes
C. They are passed on maternally
D. They are not required for survival
D. They are not required for survival
- Termites feed primarily on wood and contain symbiotic:
A. Bacteria in their intestine
B. Bacteria and archaea in their intestine
C. Fungi in their intestine
D. Protozoa, bacteria, and archaea in their intestine
E. Protozoa and fungi in their intestine
D. Protozoa, bacteria, and archaea in their intestine
- In the termite gut, what leads to the production of acetate?
A. Lactate B. Pyruvate C. Carbon dioxide D. Hydrogen E. Glucose
B. Pyruvate
C. Carbon dioxide
D. Hydrogen
- If termites are fed antibiotics they cannot survive because:
A. Their cellulase-producing bacterial endosymbionts are killed
B. Their cellulase-producing protozoan endosymbionts are killed
C. Their nitrogenous compound-providing bacterial endosymbionts are killed
D. The methanogens in the termite intestine are killed
C. Their nitrogenous compound-providing bacterial endosymbionts are killed
- Which of the following statements about quorum-sensing is false?
A. Gram negative bacteria use small molecules called AHLs in quorum sensing
B. It correlated with population density
C. It is a type of gene regulation
D. Gram positive bacteria use small molecules called AHLs
D. Gram positive bacteria use small molecules called AHLs
- How does L. planarum reduce the virulence of S. aureus?
A. Outcompetes S. aureus
B. The production of RIP by Lactobacillus directly kills Staphylococcus
C. The production of RIP by Lactobacillus prevents toxin production by Staphylococcus
D. The Lactobacillus produces a toxin to kill Staphylococcus
C. The production of RIP by Lactobacillus prevents toxin production by Staphylococcus
