(B) Flashcards by Deleted Deleted

Which of the following can safely be ingested to fight bacterial infections?
a. antiseptics
b. disinfectants
c. phenol
d. chlorine
e. antibiotics

E. antibiotics

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Organisms that live symbiotically inside a larger organism are known as:
a. organelles
b. cyanobacteria
c. mitochondria
d. endosymbionts
e. chloroplasts

D. Endosymbionts

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The genetic expression machinery of archaea is most similar to:
a. monera
b. prokaryotes
c. bacteria
d. eukaryotes
e. mitochondria

D. Eukaryotes

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Which of these groups are considered to be microbes but NOT considered to be cells?
a. viruses
b. bacteria
c. archaea
d. protists
e. filamentous fungi

A. Viruses

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Resolution is the smallest distance by which two objects can be __________ and still be __________.
a. magnified; seen
b. separated; distinguished
c. magnified; separated
d. distinguished; separated
e. magnified; distinguished

B. separated, distinguished

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What is the total magnification of a light microscope when using a 25X ocular and 40X objective lens?
a. 15X
b. 65X
c. 400X
d. 1,000X
e. 1,200X

D. 1000X

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Which of the following would be best suited to observe the motility of microbial cells?
a. Gram stain
b. nuclear magnetic resonance
c. scanning electron microscopy
d. negative stain
e. phase-contrast microscopy

E. phase-contrast microscopy

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A fluorophore used in fluorescence microscopy that absorbs light at 260 nm would most likely fluoresce at:
a. 100 nm
b. 200 nm
c. 260 nm
d. 400 nm
e. 1000 nm

D. 400nm

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Transport __________ mediate both active and passive transport.
a. polysaccharides
b. proteins
c. lipids
d. hopanoids
e. sterols

B. proteins

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All archaeal phospholipids have a(n) __________ link between glycerol and the lipid component.
a. ester
b. ether
c. ethanolamine
d. unsaturated
e. phosphatidyl

B. ether

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All of the following statements regarding phospholipids of the cell membrane are true EXCEPT:
a. They consist of glycerol with ester links to two fatty acids and a phosphoryl group.
b. They make the membrane rigid.
c. All face each other, tail to tail.
d. The two layers in the bilayer are called leaflets.
e. They give the membrane a consistent thickness.

B. they make the membrane rigid

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The __________ is the region between the cytoplasmic membrane and the outer membrane in Gram-negative cells.
a. periplasm
b. cytoplasm
c. lysozyme
d. lipopolysaccharide
e. S-layer

A. periplasm

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Directed movements toward or away from a chemical or physical signal are known as:
a. gliding
b. flagellation
c. chemotaxis
d. locomotion
e. slime layer

C. chemotaxis

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__________ are responsible for the carbon-fixation component of the carbon cycle.
a. Heterotrophs
b. Symbionts
c. Autotrophs
d. Chemotrophs
e. Organotrophs

C. chemotrophs

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Which of the following proteins represents a coupled transport system where two molecules travel in the same direction?
a. aquaporin
b. symport
c. antiport
d. porin
e. diffusion transporters

B. symport

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When the intracellular iron concentration is low, iron-scavenging molecules called __________ are produced.
a. siderophores
b. endospores
c. heterocysts
d. mycelia
e. quorum sensors

A. siderophores

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Growth of most microorganisms occurs by:
a. budding
b. binary fission
c. replication
d. conjugation
e. transformation

B. binary fission

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The time interval required for the formation of two cells from one is called the:
a. generation time
b. growth time
c. growth rate
d. exponential rate
e. log phase

A. generation time

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What type of growth pattern is represented here: 5e3; 1e4; 2e4; 4e4; 8e4?
a. linear
b. exponential
c. lag
d. generation
e. semilogarithmic

B. exponential

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Human pathogens are:
a. halophiles
b. psychrophiles
c. mesophiles
d. thermophiles
e. extreme thermophiles

C. mesophiles

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__________ grow at temperatures as high as 121°C, which occur under extreme pressure.
a. Thermophiles
b. Extreme halophiles
c. Psychrophiles
d. Hyperpsychrophiles
e. Hyperthermophiles

E. hyperthermophiles

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Which temperature is quickly lethal to any mesophile?
a. its optimum growth temperature
b. its minimum growth temperature
c. its maximum growth temperature
d. refrigeration temperature
e. autoclave temperature

E. autoclave temperature (121 C)

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A__________ medium is one of higher osmolarity than the cell.
a. hypertonic
b. hypotonic
c. isotonic
d. defined
e. complex

A. hypertonic

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Special channels for helping water move across the membrane quickly are called
a. compatible solutes
b. osmolarity
c. aquaporins
d. mechanosensitive channels
e. chaperons

C. aquaporins

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A bacterium that thrives in your stomach is probably a(n): a. thermophile b. neutrophile c. alkaliphile d. acidophile e. psychrophile

D. acidophile

Which best describes microaerophiles? a. They require atmospheric oxygen levels to grow. b. They cannot grow in the presence of oxygen. c. They will use oxygen if it is present, but can grow even if oxygen is not present. d. They require a small amount of oxygen. e. They can't use oxygen to grow, but oxygen won't kill them.

D. they requiew a small amount of oxygen

A virus that kills bacteria is called a: a. bacteriophage b. viroid c. spore d. probiotic e. porin

A. bacteriophage

Icosahedral viral capsids take the form of a polyhedron with 20 identical _____ faces. a. helical b. filamentous c. rectangular d. triangular e. asymmetrical

D. triangular

Some viral species may derive their __________ from intracellular membranes, such as the nuclear membrane or endoplasmic reticulum. a. capsid b. genome c. envelope d. neck e. tail fibers

C. envelope

David Baltimore proposed that the primary distinction among classes of viruses was the __________ composition and the route used to express messenger RNA. a. genome b. envelope c. capsid d. tegument e. neck

A. genome

After the genome is inserted, the phage capsid remains outside, attached to the cell surface, and is referred to as: a. an envelope b. a neck c. tail fibers d. a ghost e. temperate

D. a ghost

In contrast to animal viruses and bacteriophages, plant viruses infect cells by mechanisms that do NOT involve specific: a. receptors b. membranes c. envelopes d. vectors e. hosts

A. receptors

What best defines a living organism that lives inside a larger organism? a. extremeophile b. endosymbiont c. organelle d. virus e. biofilm

b. Endosymbiont

Koch's postulates include all the following EXCEPT a. A pure culture of the pathogen must be obtained b. The pathogen must be found in every individual suffering from the disease c. The isolated pathogen must be used to infect healthy hosts d. The pathogen must be shown to contain toxins e. Healthy individuals infected with the isolated suspected pathogen must get sick with disease

D. the pathogen must be shown to contain toxins

You are observing a bacterium using a 10x ocular lens and 100x objective lens. What would the total magnification be? a. 10x b. 100x c. 1000x d. 10,000x e. 110x

1000X

In fluorescence microscopy, the specimen absorbs light and then re-emits it at a ____ energy and thus, a ____ wavelength. a) lower; shorter b) lower; longer c) higher; shorter d) higher; longer

b. Lower, Longer

Which of the following statements about membrane lipids is true? a. Lipids of bacteria have ether linkages, while those of archaea have ester linkages. b. Lipids of bacteria have ester linkages, while those of archaea have ether linkages. c. Lipids of bacteria and archaea have ester linkages. d. Lipids of bacteria and archaea have ether linkages.

B. lipids of bacteria have ester linkages, while those of archaea have ether linkages

Which of the following statements about the prokaryotic chromosome is true? a. It has a single origin of replication and the DNA is replicated unidirectionally. b. It has a single origin of replication and the DNA is replicated bidirectionally. c. It has multiple origins or replication and the DNA is replicated unidirectionally. d. It has multiple origins of replication and the DNA is replicated bidirectionally.

B. It has a single origin of replication and the DNA is replicated bidirectionally

Which of the following is NOT a component of peptidoglycan? a. N-acetyl muramic acid b. N-acetyl glucosamine c. Lipopolysaccharide d. Amino acids e. Peptide cross-links

C. lipopolysaccharide

What is the structure in prokaryotes that performs the same function as mitochondria in eukaryotes? a. Cell membrane b. Chloroplast c. Outer membrane d. Cell wall

A. cell membrane

The primary factor determining the life cycle of an animal virus is the form of its a. Receptor b. Envelope c. Capsid d. Genome

D. genome

In contrast to animal viruses and bacteriophages, plant viruses infect cells by mechanisms that do NOT involve specific a. Receptors b. Membranes c. Envelopes d. Vectors e. Hosts

A. receptors

Some bacterial viruses can insert their genome into the chromosomes of the host cell. What is the integrated genome called? a. Temperate b. Lysogen c. Oncogene d. Prophage e. Tegument

D. prophage

Microbes include members of which of the following groups? a. Bacteria, archaea, fungi, viruses b. Bacteria, animals, protozoa, fungi c. Archaea, viruses, plant, fungi d. Bacteria, archaea, protozoa, plants

A. bacteria, archaea, fungi, viruses

Which of the following combinations include only macronutrients? a. C, O, S, Zi, Mn b. H, N, K, Mg, Mo c. S, O, Mg, Ca, K d. P, H, S, Cu, Ni e. C, Ca, Co, Zi, P

C. S, O, Mg, Ca, K

Which of the following uses sunlight for energy and CO2 as a carbon source? a. Photoautotroph b. Chemoautotroph c. Photoheterotroph d. Chemoheterotroph

A. photoautotroph

Which of the following statements about microbes and temperature is false? a. Within a specific range, the microbial growth rate roughly doubles for every 10˚C rise in temperature b. Changes in temperature affects membrane fluidity, and thus nutrient transport c. Thermophiles are microbes that grow at temperatures between 40˚C and 80˚C d. Microbes have mechanisms to control their temperature

D. micorbes have mechanisms to control their temperature

A bacterium tolerates a pH range of 3-10. This represents a ___ difference in H+ ion concentration. a. 7-fold b. 70-fold c. 1,000-fold d. 10,000-fold e. 10,000,000-fold

E. 10,000,000-fold

Why can't bacteria grow in solutions with very high concentrations of sugar? a. Bacteria cannot digest pure sugar. b. Sugar raises the solution's osmolarity. c. Sugar lowers the solution's osmolarity. d. Sugar raises the pH. e. Sugar lowers the pH.

B. sugar raises the solution's osmolarity

You find that a microorganism has optimum growth at pH 9.7 and a temperature of 8˚C, this organism is a a. Neutrophilic mesophile b. Acidophilic thermophile c. Alkalophilic mesophile d. Neutrophilic psychrophile e. Alkalophilic psychrophile

E. alkalophilic psychrophile

Which of the following is/are true? a. Peripheral membrane proteins span through the membrane b. Integral membrane proteins sits on the surface of the membrane c. The membrane is a very rigid monolayer structure that encapsulates the cell d. LPS is found in gram- inner and outer membranes e. None of the above are correct

E. none of the above

Lithotrophs are organisms that feed on ____ and were discovered by ___. a. Inorganic material; Sergei Winogradsky b. Inorganic material; Dmitri Ivanovsky c. Organic material; Sergei Winogradky d. Organic material; Dmitri Ivanovsky

A. inorganic material; Sergei Winogradsky

Phospholipids can easily move ____, but rarely move ____. a. Laterally, from one leaflet to another b. From one leaflet to another, laterally c. Laterally, their fatty acid tails d. Their fatty acid tails, laterally e. From one leaflet to another, their fatty acid tails

A. laterally, from one leaflet to another

Viroids are ___ agents that infect ___. a. RNA; animals b. RNA; plants c. Protein; animals d. Protein; plants

B. RNA, plants

The largest molecule in a typical bacterial cell is: a. Phospholipid b. Membrane c. Peptidoglycan d. Ribosome e. RNA

C. Peptidoglycan

Which of the following is a micronutrient? a. carbon b. nitrogen c. sulfur d. calcium e. zinc

E. zinc

Runoff from agricultural fields, lawns, and golf courses can cause an overgrowth of microbes due to a. eutrophication. b. starvation response. c. oxidation. d. antisepsis. e. pasteurization.

A. eutrophication

What is the MOST important property that enables a lens to magnify an image? a. absorption b. fluorescence c. reflection d. refraction e. scattering

D. refraction

Suppose Pasteur's swan-necked flasks containing boiled broth became cloudy twenty-four hours after boiling. Which choice could best explain the turbidity or cloudiness in the broth without supporting spontaneous generation? a. Endospores in the broth survived boiling and grew after the broth cooled. b. Contaminating organisms in the broth killed by boiling became alive again after it cooled. c. Chemicals in the broth came together to form living organisms. d. The glass allowed light to pass through it with less interference when it was hot. e. Soluble amino acids polymerized into insoluble proteins after cooling.

A. Endospores in the broth survived boiling and grew after the broth cooled

Electron microscopes can be used to visualize all listed structures, EXCEPT: a. movement of flagellum in live cells b. ribosomes c. organelles d. cell membrane e. nucleoid

A. movement of flagellum

Which of the following statements regarding viruses is FALSE? a. Most are too small to be seen by a light microscope. b. They can pass through filters that have a pore size that blocks bacteria. c. Their genomes could be composed of DNA or RNA. d. They are smaller than prions. e. Viral particles, when pure enough, can be crystallized.

D. they are smaller than prions

All of the following are components of peptidoglycan EXCEPT a. N-acetylglucosamine. b. N-acetylmuramic acid. c. lipopolysaccharide. d. amino acids. e. peptide cross-links.

C. lipopolysaccharide

A cafeteria worker who fails to wash his hands thoroughly and fails to wear gloves inoculates a quiche with 4 E. coli cells when he uses his finger to test whether it is done. By the time you purchase the quiche, there are 64 E. coli cells in it. How many generations did the cells go through? a. 3 b. 4 c. 8 d. 32 e. 64

B. 4

Which infectious agent is identified by the nucleic acid genome being the entire infectious particle? a. viruses b. prions c. viroids d. virions e. bacteria

C. viroids

Sergei Winogradsky developed the Windogradsky column to enrich for ______ a. lithotrophs b. viruses c. eukaryotic microbes d. infectious agents e. thermophiles

A. lithotrophs

You study a bacterium that grows in low-nutrient aqueous environments. Which type of transport mechanism is required to deliver nutrients from these environments where they are at a lower concentration than inside the cell? a. aquaporins b. active transport c. facilitated diffusion d. passive diffusion e. Such bacteria cannot exist.

B. active transport

Cauliflower mosaic virus is a dsDNA pararetrovirus and thus requires which type of modified host enzyme for genome replication? a. DNA-dependent DNA polymerase b. RNA-dependent RNA polymerase c. reverse transcriptase d. polyphosphate synthase e. lipase

C. reverse transcriptase

Which of the following eukaryotic organelles are thought to be of prokaryotic origin? a. flagellum b. endosome c. nucleus d. mitochondrion e. endoplasmic reticulum

D. mitochondrion

Carl Woese's discovery replaced the classification scheme of five kingdoms with a scheme of three a. phyla. b. domains. c. classes. d. orders. e. genera.

B. domains

Which of the following is the best technique for counting only viable cells? a. direct count under microscope b. spread plate and counting colonies c. total protein measurement d. chemostat e. dry weight measurements

B. spread plate and counting colonies

When the population doubles during each given unit of time, the growth is a. linear. b. geographic. c. exponential. d. geometric. e. arithmetic.

C. exponential

A ball-shaped microbe is referred to as a a. bacillus. b. coccus. c. vibrio. d. strepto. e. spirochete.

B. coccus

The time between inoculation and the beginning of growth is usually called the ________ phase. a. lag b. early log c. late log d. stationary e. death

A. lag

A measure of the number of solute molecules in solution and is inversely related to water activity is known as a. osmolarity. b. hypertonic. c. hypotonic. d. isotonic. e. d-value.

A. osmolarity

All of the following are true about microbes and temperature EXCEPT a. Microbes have mechanisms to control their temperature. b. Temperature affects the average rate of molecular motion. c. Changes in temperature affect membrane fluidity. d. Changes in temperature affect transport. e. Every organism has an optimum temperature for growth.

A. microbes have mechanisms to control their temperature

Florence Nightingale a. solved DNA structure. b. discovered first antibiotic. c. developed pie chart of mortality data to show significance of infectious diseases in war. d. working with Pasteur proved "spontaneous generation" to be wrong. e. came up with Koch's postulates.

C. developed pie chart of mortality data to show signficance of infectious diseases in war

Cyanobacterial heterocysts function to fix atmospheric a. hydrogen sulfide. b. ammonia. c. oxygen. d. carbon dioxide. e. nitrogen.

E. nitrogen

How do we call organisms that have evolved to grow at very low temperatures? a. psychrophiles b. barophiles c. halophiles d. thermophiles e. hyperthermophile

A. psychrophiles

A microbe is commonly defined as a ________ that requires a microscope to be seen. a. virus b. bacterium c. prokaryote d. multicellular eukaryote e. living organism

E. living organism

All of the following are used by prokaryotic cells for attaching to solid surfaces EXCEPT a. endospore. b. capsule. c. stalks. d. fimbriae. e. pili.

A. endospore

The first person to visualize individual microbial cells was a. Antonie van Leeuwenhoek. b. Robert Koch. c. Louis Pasteur. d. Alexander Fleming. e. Sergei Winogradsky.

A. Antonie van Leeuwenhoek

You have isolated a bacterium that you believe to be the causative agent of a new disease in frogs. What step would not be a part of study to prove Koch's postulates? a. Determine the shape of the bacterial cells. b. Inject the bacteria into a healthy frog. c. Isolate the bacterium from a sick frog. d. Show that the bacterium is present in sick frogs. e. Grow a pure culture of the bacterium outside the frog.

A. determine the shape of the bacterial cells

When a bacterial cell is infected, the viral capsid a. enters the host cell with the viral genome. b. remains on the outside of the host cell as a "ghost". c. enters the host cell separately from the viral genome. d. is released to attach to and inject another host cell. e. becomes part of the host cell membrane.

B. remains on the outside of the host cell as a "ghost"

Which of the following are responsible for the CO2-fixation component of the carbon cycle? a. heterotrophs b. symbionts c. autotrophs d. chemotrophs e. organotrophs

C. autotrophs

(B) Flashcards

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