Frage 1
Frage
A substance found in the plasma membrane of eukaryotic cells but not the plasma membrane of most prokaryotic cells is ______.
Antworten
-
cholesterol
-
phospholipids
-
proteins
-
phospholipids and proteins
-
cholesterol, phospholipids, and proteins
Frage 2
Frage
An acidophile is an organism that ____.
Antworten
-
ferments glucose to lactic acid
-
requires organic acids for growth
-
grows at high salt concentrations
-
ferments sugars to acids
-
tolerate exposure to low pH values without being killed
Frage 3
Frage
Bacteria that use O2 for aerobic respiration when it is present, but also grow in its absence by fermenting substrates are called ____.
Antworten
-
obligate aerobes
-
facultative anaerobes
-
microaerophile
-
aerotolerant anaerobes
-
obligate anaerobes
Frage 4
Frage
Bacteria that lack cell walls readily lyse in _____ solution.
Antworten
-
hypotonic
-
hypertonic
-
isotonic
-
hypertonic and hypotonic
-
none of the above
Frage 5
Frage
Bacteria in the logarithmic phase of growth ______.
Antworten
-
double at a constant rate called the generation time
-
increase 10-fold in number with each generation
-
form new cells at the same rate that old cells die
-
- double at a constant rate called the generation time
- form new cells at the same rate that old cells die
-
none of the above
Frage 6
Frage
Capsules are important virulence factors for bacteria because they ____.
Antworten
-
are antiphagocytic factors
-
can mediate the attachment of bacteria to surfaces (including host surfaces)
-
are endotoxins
-
- are antiphagocytic factors
- can mediate the attachment of bacteria to surfaces (including host surfaces)
-
- are antiphagocytic factors
- are endotoxins
Frage 7
Frage
Chains of cocci are called _______.
Antworten
-
streptococci
-
diplococci
-
staphylococci
-
sarcinae
-
coccobacilli
Frage 8
Frage
Ignatz Semmelweis discovered that the incidence of peurperal (childbirth) fever could be lowered dramatically by ______.
Frage 9
Frage
In glycolysis, one molecule of glucose is converted into _____.
Frage 10
Frage
Media that are specifically designed to grow anaerobic bacteria are called ____ media.
Antworten
-
reducing
-
differential
-
selective
-
chemically defined
-
enrichment
Frage 11
Frage
Microorganisms that grow only at temperatures between -10 and 20 C are called _____.
Antworten
-
thermophiles
-
mesophiles
-
psychrophiles
-
psychrotrophs
-
extreme thermophiles
Frage 12
Frage
Negative stains _______.
Antworten
-
stain the background, not the cell
-
are used to detect capsules
-
stain gram-negative bacteria but not gram-positive bacteria
-
- stain the background, not the cell
- are used to detect capsules
-
- stain the background, not the cell
- stain gram-negative bacteria but not gram-positive bacteria
Frage 13
Frage
Siderophores are _______.
Antworten
-
toxic oxygen metabolites that form in cells
-
compounds secreted by bacteria that solubilize ferric ions
-
organic growth factors that have to be added to bacterial media
-
electron transport carriers in bacteria
-
none of the above
Frage 14
Frage
The cell wall component that protects bacteria against lysis by osmotic pressure is _________.
Antworten
-
peptidoglycan
-
teichoic acid
-
lipopolysaccharide
-
phospholipid
-
porins
Frage 15
Frage
The conversion of glucose to lactic acid by oral streptococci and lactobacilli _________.
Antworten
-
produces only 2 molecules of ATP for each molecule of glucose degraded
-
is an important event in the formation of dental caries
-
is an example of fermentation
-
- produces only 2 molecules of ATP for each molecule of glucose degraded
- is an example of fermentation
-
- produces only 2 molecules of ATP for each molecule of glucose degraded
- is an important event in the formation of dental caries
- is an example of fermentation
Frage 16
Frage
The outer membrane of gram-negative bacteria contains ________.
Frage 17
Frage
The primary function of the cytoplasmic membrane in prokaryotes is to ________.
Frage 18
Frage
The total number of viable bacteria in 1 ml of a broth culture can be determined by ______.
Antworten
-
the streak plate technique
-
a standard plate count
-
a direct microscope count
-
- a standard plate count
- a direct microscope count
-
- the streak plate technique
- a standard plate count
- a direct microscope count
Frage 19
Frage
The degree of relatedness between two microorganisms can best be determined by ________.
Antworten
-
biochemical tests
-
morphological features
-
DNA hybridization
-
differential staining
-
DNA base composition
Frage 20
Frage
The enzyme that converts H2O2 into H2O and O2 is called _____.
Antworten
-
lysozyme
-
superoxide dismutase
-
catalase
-
peroxidase
-
oxygenase
Frage 21
Frage
The newly published Bergey's Manual of Systemic Bacteriology, 2nd Edition classifies prokaryotes into taxonomic units primarily based upon _____.
Frage 22
Frage
The Three Domain System for the classification of microorganisms places _____.
Antworten
-
prokaryotes into two domains called Protista and Bacteria
-
domains over Kingdoms
-
all eukaryotic cells into a single domain called Eukarya
-
- domains over kingdoms
- all eukaryotic cells into a single domain called Eukarya
-
- prokaryotes into two domains called Protista and Bacteria
- domains over kingdoms
- all eukaryotic cells into a single domain called Eukarya
Frage 23
Frage
The transfer of DNA from one bacterium to another by a bacteriophage is called ________.
Antworten
-
conjugation
-
transformation
-
transportation
-
transduction
-
lysogeny
Frage 24
Frage
The pour-plate technique differs from the spread-plate technique (for doing a standard plate count) in that ______.
Antworten
-
serial dilutions are prepared in the pour-plate method but not the spread-plate method
-
colonies form in the agar and on the surface in the pour-plate method, but only on the surface with the spread plate method
-
the bacterial sample is mixed into molten agar in the pour plate method, but are spread over the surface of hardened agar in the spread plate method
-
- colonies form in the agar and on the surface in the pour-plate method, but only on the surface with the spread plate method
- the bacterial sample is mixed into molten agar in the pour plate method, but are spread over the surface of hardened agar in the spread plate method
-
- serial dilutions are prepared in the pour-plate method but not the spread-plate method
- colonies form in the agar and on the surface in the pour-plate method, but only on the surface with the spread plate method
- the bacterial sample is mixed into molten agar in the pour plate method, but are spread over the surface of hardened agar in the spread plate method
Frage 25
Frage
The process of destroying all microbial life forms is called ______.
Antworten
-
sterilization
-
antisepsis
-
disinfection
-
sanitization
-
bacteriostasis
Frage 26
Frage
Which of the following statements about facilitated transport is (are) true?
Antworten
-
it requires ATP or other high energy compound
-
it requires a transporter protein
-
It accumulates substrates to higher concentration inside a cell than outside a cell
-
- it requires a transporter protein
- It accumulates substrates to higher concentration inside a cell than outside a cell
-
- it requires ATP or other high energy compound
- it requires a transporter protein
- It accumulates substrates to higher concentration inside a cell than outside a cell
Frage 27
Frage
Which of the following statements about endospores is FALSE?
Antworten
-
they are reproductive structures
-
they are much more resistant to killing than vegetative cells
-
they can germinate and cause food spoilage or disease
-
Bacillus and Clostridium are the only medically important bacteria to produce endospores
-
they can survive in soil for a hundred years or more
Frage 28
Frage
Which of the following statements about eukaryotic ribosomes is (are) true?
Antworten
-
they are smaller than prokaryotic ribosomes
-
they can bind to the endoplasmic reticulum
-
they are the sites of oxidative phosphorylation in eukaryotic cells
-
- they are smaller than prokaryotic ribosomes
- they can bind to the endoplasmic reticulum
-
- they are smaller than prokaryotic ribosomes
- they are the sites of oxidative phosphorylation in eukaryotic cells
Frage 29
Frage
Which of the following statements best explains why gram-negative bacteria are more resistant than gram-positive bacteria to most antibiotics and detergents?
Antworten
-
gram-negative bacteria have less peptidoglycan in their cell wall
-
gram-positive bacteria have teichoic acids in their cell wall
-
antibiotics and detergents often have difficulty penetrating the outer membrane of gram-negative bacteria
-
gram-negative bacteria have a different cytoplasmic membrane structure
-
none of the above
Frage 30
Frage
Which of the following statements about eukaryotic cells is FALSE? If none are false, choose "none of the above."
Antworten
-
they may be motile by either flagella or cilia
-
all eukaryotic cells have cell walls
-
their nuclear membrane has pores in it
-
the nuclear membrane of eukaryotes is contiguous with the endoplasmic reticulum
-
none of the above
Frage 31
Frage
Which of the following statements about microbial growth is FALSE?
Antworten
-
most microorganisms grow very rapidly
-
growth is determined by the size of the individual cells
-
bacteria grow by binary fission
-
unchecked microbial growth can cause food spoilage and disease
-
microorganisms can form very large populations of cells
Frage 32
Frage
Which of the following statements about porins is true?
Antworten
-
they form pores (channels) in the outer membrane of gram-negative bacteria
-
they are found in gram-positive bacteria
-
they allow nutrients to pass through the cytoplasmic membrane of eukaryotes
-
they are membrane-bound organelles found in eukaryotic cells
-
none of the above
Frage 33
Frage
Which of the following statements about lipopolysaccharides is FALSE?
Antworten
-
they are also called endotoxin
-
they cause fever
-
the O-specific polysaccharide is the toxic component
-
they consist of three disscernable regions called lipid A, core polysaccharide, and O-specific polysaccharide
-
they are inactivated by autoclaving
Frage 34
Frage
Which of the following statements about peptidoglycan is FALSE?
Antworten
-
it is present in gram-negative bacteria
-
it is present in gram-positive bacteria
-
it gives bacterial cells their shape and rigidity
-
it completely surrounds bacterial cells
-
it is a large polymer composed solely of amino acids
Frage 35
Frage
Which of the following is NOT a mechanism by which bacteria exchange genetic material?
Antworten
-
conjugation
-
transformation
-
transduction
-
crossing over
Frage 36
Frage
Transcription is _________.
Frage 37
Frage
Which of the following are eukaryotes?
Antworten
-
Bacteria
-
Archaea
-
Fungi
-
Viruses
-
None of the above
Frage 38
Frage
Which of the following statements about fermentations is FALSE?
Antworten
-
they occur in the absence of oxygen
-
they use an organic molecule as the final electron acceptor
-
they release energy from a sugar or other organic molecule
-
they are considerable less efficient than aerobic respiration
-
they require and electron transport chain
Frage 39
Frage
Which of the following statements about fimbriae is FALSE?
Antworten
-
they are thin, hairlike filaments
-
they can act as adhesins
-
they give bacterial cells motility
-
there may be as many as 100-200 fimbriae per cell
-
they are important virulence factors for some pathogenic bacteria
Frage 40
Frage
Which of the following statements about prokaryotic cells is (are) true?
Antworten
-
they have membrane bound organelles in their cytoplasm
-
their nucleus lacks a membrane and is in direct contact with the cytoplasm
-
their cytoplasm has a microtubule cytoskeleton
-
- they have membrane bound organelles in their cytoplasm
- their nucleus lacks a membrane and is in direct contact with the cytoplasm
-
- they have membrane bound organelles in their cytoplasm
- their cytoplasm has a microtubule cytoskeleton
Frage 41
Frage
Which of the following microscopes has the most resolving power and gives the highest magnification?
Frage 42
Frage
Which of the following is the correct order of the four steps in the Gram stain?
Antworten
-
1) safranin 2) iodine 3) alcohol 4) crystal violet
-
1) iodine 2) safranin 3) alcohol 4) crystal violet
-
1) crystal violet 2) iodine 3) alcohol 4) safranin
-
1) crystal violet 2) alcohol 3) iodine 4) safranin
-
1) alcohol 2) safranin 3) iodine 4) crystal violet
Frage 43
Frage
Which of the following statements about a typical cytoplasmic membrane under normal physiological conditions is NOT true?
Antworten
-
If you believe none of the other 3 choices is a correct answer to the question, choose this choice
-
Membrane proteins float in the lipids of a cytoplasmic membrane under normal conditions
-
The lipids in a cytoplasmic membrane typically have the consistency of a light oil
-
Membrane proteins can freely flip-flop from one layer (leaflet) of a membrane to the other
Frage 44
Frage
The individual microbial species in a mixed sample of microbes can be separated from each other and grown in pure culture by ______.
Antworten
-
plating serial dilution of the sample on agar media
-
the streak plate technique
-
none of the above
-
- plating serial dilution of the sample on agar media
-the streak plate technique
Frage 45
Frage
The number of cells in an actively growing microbial population doubles with each succeeding generation. A doubling of cell number with each generation is commonly called arithmetic growth.
Antworten
-
The first statement is false; the second statement is false
-
The first statement is true; the second statement is true
-
The first statement is true; the second statement is false
-
The first statement is false; the second statement is true
Frage 46
Frage
Which of the following is NOT a possible reason for the occurrence of a stationary phase in a bacterial growth curve?
Antworten
-
none of the above
-
accumulation of waste products in the growth medium
-
depletion of nutrients in the growth medium
-
the generation time of the dividing organisms
-
a drop in the pH of the growth medium
Frage 47
Frage
The cytoskeleton of prokaryotic cells is _______.
Frage 48
Frage
Which of the following microbes produces a slime layer that allows it to colonize devices implanted in skin such as a catheter?
Antworten
-
mycobacteria
-
Bacillus species
-
Streptococci
-
Staphylococci
Frage 49
Frage
The term aciduric means that a microbe _____.
Antworten
-
converts organic acids into CO2 and H2O
-
survives exposure to low pH without being killed
-
grows on amino acids instead of sugars
-
ferments sugars to acids
Frage 50
Frage
Which of the following statements about prokaryotic flagella is true?
Antworten
-
none of the above
-
they are composed of 3 parts: a long filament, a hook, and a basal body
-
their primary function is to mediate the attachment of prokaryotic cells to other cells or surfaces
-
they generate motion by a whip-like or wave motion
Frage 51
Frage
The theory of spontaneous generation was finally disproven once and for all by _________.
Antworten
-
Francesco Redi
-
Paul Ehrlich
-
Robert Kock
-
Louis Pasteur
-
Joseph Lister
Frage 52
Frage
Which of the following statements best explains why a cell would use a Na+ ion-glucose symporter to transport glucose into a cell?
Antworten
-
none of the above
-
the symporter is used to equalize the concentration of glucose inside and outside the cell
-
the symporter is used to transport glucose into a cell that has a higher concentration of glucose inside the cell than outside the cell
-
The symporter is used to transport glucose into a cell that has a lower concentration of glucose inside the cell than there is outside the cell
Frage 53
Frage
The component of the gram-negative outer cell wall membrane makes it a rigid membrane is:
Frage 54
Frage
When glucose is fermented to lactic acid by a microbe, most of the original energy (calories) in the glucose molecule is _____.
Frage 55
Frage
Viable (standard) plate counts are done by _______.
Antworten
-
none of the above
-
making serial 1/10 dilutions of a bacterial sample and plating a known aliquot of each dilution on an agar growth medium
-
streaking the bacterial sample on a microbial growth medium
-
counting the number of cells in a known dilution of a bacterial sample using a microscope and a Petroff-Hauser counter
Frage 56
Frage
Transmission electron microscopes _______.
Antworten
-
are used to view the three dimensional structure of individual proteins and other macromolecules
-
have a higher magnification than light microscopes
-
none of the above
-
- are used to view the three dimensional structure of individual proteins and other macromolecules
- have a higher magnification than light microscopes
Frage 57
Frage
Which of the following is the least toxic form of oxygen?
Antworten
-
molecular oxygen
-
singlet oxygen
-
peroxide anion
-
superoxide anion
-
hydroxyl free radical
Frage 58
Frage
The chances of isolating a pathogen that is present in small numbers from a sample that contains a large total number of microbes and many different microbial species can be greatly increased by using a ____.
Antworten
-
defined culture medium
-
complex culture medium
-
selective culture medium
-
reducing culture medium
-
candle jar
Frage 59
Frage
Which of the following statements about preserving food by freezing is true?
Antworten
-
it preserves food by its low temperature and making liquid water unavailable to the microbial cells
-
it kills all of the vegetative microbial cells in food
-
none of the above
-
- it preserves food by its low temperature and making liquid water unavailable to the microbial cells
- it kills all of the vegetative microbial cells in food
Frage 60
Frage
The basic structure of most cytoplasmic membranes is a lipid bilayer that contains embedded proteins. The embedded proteins in a cytoplasmic membrane are the driving force for formation of the membrane.
Antworten
-
The first statement is false; the second statement is false
-
The first statement is true; the second statement is true
-
The first statement is true; the second statement is false
-
The first statement is false; the second statement is true
Frage 61
Frage
Which of the following stains is commonly used to detect the presence of a capsule around a microbe?
Antworten
-
negative stain
-
endospore stain
-
acid-fast stain
-
gram stain
Frage 62
Frage
The process of sporulation produces 1 endospore from a bacterial cell. Most pathogenic bacteria produce endospores when exposed to harsh conditions.
Antworten
-
The first statement is false; the second statement is false
-
The first statement is true; the second statement is true
-
The first statement is true; the second statement is false
-
The first statement is false; the second statement is true
Frage 63
Frage
Which of the following statements is true of the prokaryotes?
Antworten
-
none of the above
-
their genetic material is surrounded by a double membrane
-
They lack or have a simple cytoskeleton in their cytoplasm
-
They have specialized membrane-bound organelles in their cytoplasm
Frage 64
Frage
The conditions for historical pasteurization are _________.
Frage 65
Frage
Which of the following eukaryotic organelles contain a circular molecule of DNA and prokaryotic ribosomes?
Frage 66
Frage
The endoplasmic reticulum of eukaryotic cells _________.
Antworten
-
none of the above
-
functions as a transport network for newly synthesized proteins
-
is continuous with the nuclear membrane
-
often has ribosomes bound to it
Frage 67
Frage
Which of the following is NOT a function of the cytoskeleton in eukaryotic cells?
Antworten
-
none of the above
-
it enables cytoplasmic streaming and the movement of organelles in cytoplasm
-
it anchors cytoplasmic organelles
-
it carries out the degradation of old and defective proteins in the cytoplasm
Frage 68
Frage
Teichuronic acids are:
Antworten
-
none of the above
-
produced by gram-positive bacteria when they are grown in phosphate-deficient media
-
also called the O-specific antigen
-
a component of lipopolysaccharides
Frage 69
Frage
Streptococci divide ______.
Frage 70
Frage
the formation of phosphoenolpyruvate by glycolysis and the transfer of its phosphate group to ADP is an example of _________.
Frage 71
Frage
Reducing media are used to grow ________.
Antworten
-
microaerophilic microbes
-
obligate anaerobes
-
chemoautotrophs
-
capnophilic microbes
Frage 72
Frage
Protozoa historically ___________.
Frage 73
Frage
The Shaeffer-Fulton endospore stain is useful in the identification of _________.
Frage 74
Frage
Peptidoglycan is __________________.
Antworten
-
composed of long polysaccharide chains cross-linked by amino acids
-
found only in gram-positive bacteria
-
none of the above
-
- composed of long polysaccharide chains cross-linked by amino acids
- found only in gram-positive bacteria
Frage 75
Frage
Motile bacteria have the ability to detect and respond to a concentration gradient of a chemoattractant in their growth environment. Motile bacteria swim in a straight line when they rotate their flagella counterclockwise.
Antworten
-
The first statement is false; the second statement is false
-
The first statement is true; the second statement is true
-
The first statement is true; the second statement is false
-
The first statement is false; the second statement is true
Frage 76
Frage
Passive transport _________.
Frage 77
Frage
A fastidious microbe is a microbe that ________.
Antworten
-
requires elevated levels of CO2 in order to grow
-
does not produce a bad odor when it is grown in culture
-
has special nutrient requirements
-
cannot be grown on artificial media
Frage 78
Frage
Microbes are ecologically important because they _______.
Antworten
-
none of the above
-
are the basis for the food chain in the oceans
-
recycle bound vital elements to a form that can be used again
-
produce most of the oxygen in the atmosphere
Frage 79
Frage
Long, straight, hair-like appendages on the surface of bacterial cells that are not involved in motility are called ______.
Antworten
-
axial filaments
-
microfilaments
-
fimbriae
-
microtubules
-
cilia
Frage 80
Frage
An obligate anaerobe produces adequate or high levels of __________.
Antworten
-
none of the above
-
peroxidase
-
catalase
-
superoxide dismutase
Frage 81
Frage
Indirect methods for measuring microbial growth include all of the following EXCEPT ___________.
Frage 82
Frage
Bacteria grow by a simple process called binary fission. The generation time for microbial cells is usually 2 or 3 times longer than the generation time for eukaryotic cells.
Antworten
-
The first statement is false; the second statement is false.
-
The first statement is true; the second statement is true.
-
The first statement is true; the second statement is false.
-
The first statement is false; the second statement is true.
Frage 83
Frage
Eukaryotic flagella _______.
Antworten
-
generate motion by rotating like a turbine
-
are long cytoplasmic projections that contain microtubules
-
none of the above
-
- generate motion by rotating like a turbine
- are long cytoplasmic projections that contain microtubules
Frage 84
Frage
Cells maintain an electrical gradient of -70 mV across their cytoplasmic membrane by selectively maintaining a high concentration of _____ in their cytoplasm and by having protein channels in their cytoplasmic membrane that are freely permeable to _____.
Antworten
-
Na+ ions / Na+ ions
-
K+ ions / Na+ ions
-
K+ ions / K+ ions
-
Na+ ions / K+ ions
Frage 85
Frage
Bacteriostasis means that _______.
Antworten
-
bacterial growth is inhibited, but the bacteria are not killed
-
bacteria are growing (multiplying)
-
all bacteria are killed
-
the number of live microbes have been reduced to a safe level
Frage 86
Frage
Immunofluorescence tests require ___________.
Antworten
-
a phase contrast microscope
-
specific antibodies to a microbe
-
none of the above
-
- specific antibodies to a microbe
- a phase contrast microscope
Frage 87
Frage
Bacterial cells that are treated with penicillin are killed by _________.
Frage 88
Frage
All of the following statements are true about all eukaryotic cells EXCEPT one. Which one is the exception?
Antworten
-
none of the above
-
they have a complex cytoskeleton
-
they have membrane-bound organelles in their cytoplasm
-
they have membrane around their nucleus
-
they have a cell wall
Frage 89
Frage
Lipid enveloped viruses are usually more resistant to inactivation (killing) by most antimicrobial agents than naked viruses. The presence of organic matter, grease and/or dirt can interfere with the killing action of an antimicrobial agent.
Antworten
-
The first sentence is true; the second sentence is false
-
The first sentence is false; the second sentence is true
-
The first sentence is false; the second sentence is false
-
The first sentence is true; the second sentence is true
Frage 90
Frage
All of the following are required for a cell to break down glucose by aerobic respiration, EXCEPT for ________.
Frage 91
Frage
Microorganisms in biofilms:
Antworten
-
develop as porous, mushroom-like structures when there are lots of nutrients present in the biofilm
-
typically have the same sensitivity to antibiotics as they do when growing freely in broth culture
-
none of the above
-
- develop as porous, mushroom-like structures when there are lots of nutrients present in the biofilm
- typically have the same sensitivity to antibiotics as they do when growing freely in broth culture
Frage 92
Frage
Transposons _________.
Antworten
-
can cause frameshift mutations
-
are small pieces of DNA that can move from one location in a DNA molecule to another location
-
on the same or a different chromosome
-
- can cause frameshift mutations
- are small pieces of DNA that can move from one location in a DNA molecule to another location
-
none of the above
Frage 93
Frage
Transduction is the transfer of genes from one bacterium to another by ________.
Frage 94
Frage
The scanning electron microscope is primarily used to visualize the _______.
Antworten
-
structure of atoms
-
internal structures of cells
-
structure of large molecules such as proteins
-
surface of cells and objects
Frage 95
Frage
The region of logarithmic growth in a bacterial growth curve _________.
Antworten
-
can be used to determine the generation time of a microbe
-
is a region where the number of new cells being formed is equal to the number of cells that are dying
-
- is a region where the number of new cells being formed is equal to the number of cells that are dying
- can be used to determine the generation time of a microbe
-
none of the above
Frage 96
Frage
Non-membranous organelles in eukaryotic cells include all of the following EXCEPT:
Antworten
-
ribosomes
-
peroxisomes
-
centrioles
-
proteosomes
Frage 97
Frage
The purpose of iodine in the Gram stain is to __________.
Antworten
-
stain the cells purple
-
stain cells a light red color
-
enhance staining of gram-positive bacteria with crystal violet
-
enhance the staining of gram-negative bacteria with safranin
Frage 98
Frage
The theory of biogenesis was proven by ________.
Antworten
-
Alexander Fleming
-
Robert Koch
-
Louis Pasteur
-
John Needham
Frage 99
Frage
The genetic material of prokaryotic cells is __________.
Antworten
-
attached to the cell's cytoskeleton
-
usually a single circular molecule of DNA
-
enclosed in a porous membrane
-
none of the above
Frage 100
Frage
A chemoautotroph uses ______ as a carbon source and ______ as an energy source.
Frage 101
Frage
The structural polymer that protects bacterial cells from osmotic lysis is the _______.
Antworten
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cytoplasmic membrane
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glycocalyx
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peptidoglycan
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capsule
Frage 102
Frage
The first person to prove that microbes can cause infectious disease in humans was _______.
Antworten
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Antoni van Leeuwenhock
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Robert Koch
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Louis Pasteur
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Francesco Redi
Frage 103
Frage
Snapping division in prokaryotic cells produces _______.
Antworten
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packets of 8 cocci
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chains of rods
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spirochetes
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V and Y shapes
Frage 104
Frage
Osmotic pressure is defined as the hydrostatic pressure required to ______.
Frage 105
Frage
Nucleosomes are _________.
Antworten
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present in both prokaryotic and eukaryotic cells
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complexes of DNA and histones
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extra-chromosomal pieces of DNA
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- present in both prokaryotic and eukaryotic cells
- complexes of DNA and histones
Frage 106
Frage
Microbes are beneficial because they _______.
Frage 107
Frage
The conversion of nitrogen gas (N2) into ammonia _______.