302 Q Flashcards
1
Q
Mannitol salt agar (MSA) only allows the growth of halophiles (salt-loving microbes). Among the halophiles, mannitol fermenters release acid that turns the pH indicator yellow; mannitol nonfermenters leave the medium red. Onto MSA you inoculate a halophilic mannitol nonfermenter and a nonhalophilic mannitol nonfermenter. Here the medium acts as a \_\_\_\_\_\_\_\_\_\_ medium. Differential Selective Selective and differential Enrichment
A
Selective
2
Q
Which of the following forms of bacterial respiration yields the least amount of ATP? Anaerobic respiration. Fat oxidation. Glucose fermentation. Aerobic respiration.
A
Glucose fermentation.
3
Q
Which of the following characteristics is not true of alpha haemolysis?
Complete haemolysis of RBCs (Red Blood Cells).
Narrow zone of clearing.
Clearing displays indefinite margin.
Produces a greenish zone.
A
Complete haemolysis of RBCs (Red Blood Cells).
4
Q
Which of the following characteristics is not true of beta haemolysis? Sharply defined zone of clearing Colourless zone of clearing Narrow zone of clearing (<2mm) Complete haemolysis
A
Narrow zone of clearing (<2mm)
5
Q
The fruiting body of a mushroom is called Basidiocarps Plasmodiocarps Ascocarps Sorocarps
A
Basidiocarps
6
Q
What is the purpose of a Oxidase test?
What is the purpose of a Oxidase test?
To test for the presence of the enzyme catalase.
To distinguish oxidative from fermentative metabolism.
To test if a bacteria is an obligate anaerobe
To test for the presence of cytochrome C.
A
To test for the presence of cytochrome C
7
Q
Mannitol salt agar (MSA) only allows the growth of halophiles (salt-loving microbes); nonhalophiles will not grow. Among the halophiles, mannitol fermenters will produce acid that turns the pH indicator yellow; mannitol nonfermenters leave the medium red. Onto MSA you inoculate a halophilic mannitol fermenter and a halophilic mannitol nonfermenter. In this case, the medium is acting as (a) \_\_\_\_\_\_\_\_\_\_ medium(s). Differential Selective Selective and differential Enrichment
A
Differential
8
Q
Bat sites usually harbor the following primary pathogenic fungus:
Bat sites usually harbor the following primary pathogenic fungus:
Phaeoannellomyces werneckii
Madurella mycetomatis
Paracoccidioides brasiliensis
Histoplasma capsulatum
A
Histoplasma capsulatum
9
Q
Anaerobic respiration is distinguished from aerobic respiration by:
Anaerobic respiration is distinguished from aerobic respiration by:
Molecules other than O2 act as terminal electron acceptors.
Net oxidation of substrates.
ATP production by substrate level phosphorilation.
All of the above.
A
Molecules other than O2 act as terminal electron acceptors.
10
Q
The cytoplasm is _______ .
The cytoplasm is _______ .
A selectively permeable barrier composed of hydrophillic and hydrophobic fatty acids.
The substance in which the nucleoid, ribosomes & inclusion bodies
are suspended.
The site of protein synthesis.
All of the above.
A
The substance in which the nucleoid, ribosomes & inclusion bodies
are suspended.
11
Q
. You inoculated and then incubated an oxidation/fermentation (OF) test over the past 5 days. You return to find that the top third of the media has transformed from green to yellow. From this you derive that the inoculated bacteria \_\_\_\_\_\_\_\_\_ . Contains the enzyme Oxidase Is a mannitol fermenter Utilises an oxidative metabolism Utilises a fermentative metabolism
A
Utilises an oxidative metabolism
12
Q
Which culture media is used to isolate staphylococci?
Which culture media is used to isolate staphylococci?
Blood agar
Mannitol salt agar
Chocolate agar
MacConkey agar
A
Mannitol salt agar
13
Q
. Mannitol salt agar (MSA) only allows the growth of halophiles (salt-loving microbes). Among the halophiles, mannitol fermenters release acid that turns the pH indicator yellow; mannitol nonfermenters leave the medium red. Onto MSA you inoculate a halophilic mannitol fermenter, a nonhalophilic mannitol fermenter, and a halophilic mannitol nonfermenter. Thus, the medium is acting as a \_\_\_\_\_\_\_\_\_\_ medium. Differential Selective Enrichment Selective and differential
A
Selective and differential
14
Q
The bread mold Rhizopus stolonifer belongs to which of the following fungal divisions? Ascomycota Chytridiomycota Microsporidia Zygomycota
A
Zygomycota
15
Q
Select the corrent order in which biofilms form:
Active dispersal, Development, Colonisation, Reversable adhesion, Irreversible adhesion.
Reversible adhesion, Irreversible adhesion, Colonisation, Development, Active dispersal
Development, Active dispersal, Colonisation, Reversable adhesion, Irreversible adhesion.
Reversible adhesion, Irreversible adhesion, Development, Colonisation, Active dispersal.
A
Reversible adhesion, Irreversible adhesion, Colonisation, Development, Active dispersal
16
Q
Fungi can be distinguished from algae due to
Fungi can be distinguished from algae due to
the presence of a chitinous cell wall
the presence of a visable nucleus
the presence of a cellulosic cell wall
The absence of mitochondria
A
the presence of a chitinous cell wall
17
Q
Fungi usually store the reserve food material in the form of
Fungi usually store the reserve food material in the form of
Starch
Glycogen
Lipid
Protein
A
Glycogen
18
Q
Which of the following is not true of haemolysis?
Which of the following is not true of haemolysis?
Beta haemolysis produces a clear zone around the bacterial colony.
Alpha haemolysis produces greenish discolouration of RBCs around the bacterial colony.
Gamma haemolysis produces no colour change around the bacterial colony.
Haemolytic function is associated with the enzyme streptokinase.
A
Haemolytic function is associated with the enzyme streptokinase.
19
Q
What are the three basic steps of conventional PCR?
What are the three basic steps of conventional PCR?
Denature, anneal, & strand displacement
Strand displacement, synthesis & release
Reverse-transcription, anneal & extend
Denature, anneal & extension
A
Denature, anneal & extension
20
Q
Fungi are major causes of plant diseases. are pest organisms that have no commercial value Only (i.) is true. Only (ii.) is true Neither (i.) or (ii.) are true Both (i.) and (ii.) are true
A
Only (i.) is true
21
Q
Which ingredient makes MacConkey agar differential? Peptone Agar Lactose Bile salts
A
Lactose
22
Q
If you are designing an experiment involving a chemolithotrophic autotroph; which of the following would be most essential to maintaining growth of the organism?
A continual supply of abundant oxygen
A nutrient medium containing glucose
Keeping the cultures at 37°C
A source of reduced inorganic compound such as NH4
A
A source of reduced inorganic compound such as NH4
23
Q
Which by-product of bacterial fermentation is responsible for dental disease?
Which by-product of bacterial fermentation is responsible for dental disease?
Lactic acid.
NADH.
Ethanol.
Pyruvate
A
Lactic acid.
24
Q
Blood agar is often used to differentiate between:
Bacteria that absorb oxygen and those that do not.
Salt sensitive and non-salt sensitive microbes.
Types of hemolysis the bacteria may produce.
All of the above.
A
Types of hemolysis the bacteria may produce.
25
```
Fungi __________.
Fungi __________.
have cell walls of peptidoglycan
are procaryotic
are photosynthetic
secrete extracellular enzymes to breakdown nutrients
```
secrete extracellular enzymes to breakdown nutrients
26
An organism is capable of oxidizing H2S and using the energy obtained from the reaction to reduce carbon dioxide. Which type of metabolism does this organism possess?
An organism is capable of oxidizing H2S and using the energy obtained from the reaction to reduce carbon dioxide. Which type of metabolism does this organism possess?
Photolithotrophic autotroph
Chemoorganotrophic heterotroph
Photoorganotrophic heterotroph
Chemolithotrophic autotroph
Chemolithotrophic autotroph
27
n a bacterial colony, the youngest and most rapidly growing cells are _______ .
In a bacterial colony, the youngest and most rapidly growing cells are _______ .
Found at its leading edge.
Found at its centre.
Found evenly distributed throughout the colony.
Impossible to locate
Found at its leading edge.
28
Many Gram negative bacteria can grow on MacConkey agar but the growth of most Gram positive bacteria is inhibited. What ingredient is used in MacConkey agar to cause this inhibition?
Many Gram negative bacteria can grow on MacConkey agar but the growth of most Gram positive bacteria is inhibited. What ingredient is used in MacConkey agar to cause this inhibition?
Agar
Antibiotics
Lactose
Bile salts
Bile salts
29
Which of the following is not an example of a biofilm?
Which of the following is not an example of a biofilm?
Dental plaque.
A single bacterial cell growing on an agar surface.
Toilet bowl scum.
Organisms that colonize indwelling medical devices.
A single bacterial cell growing on an agar surface.
30
Which of the following bacterial respirations gives the maximum energy yield?
Which of the following bacterial respirations gives the maximum energy yield?
Anaerobic respiration.
EMP pathway.
Aerobic respiration.
Fermentation
Aerobic respiration.
31
Biofilms are organised aggregates of bacteria that may:
Biofilms are organised aggregates of bacteria that may:
Protect one another.
Communicate with one another.
Form differentiated structures with specialised functions.
All of the above.
All of the above.
32
Select the correct statement from the following:
Select the correct statement from the following:
Plasmids are able to replicate independently of the bacterial
chromosome.
Plasmids are small, closed, circular, double stranded DNA.
Plasmids can carry genes that confer a selective
trait and move between different bacteria.
All of the above.
All of the above.
33
________ exhibit yeast-like growth at human body temperatures and mold-like growth at room temperature
________ exhibit yeast-like growth at human body temperatures and mold-like growth at room temperature
Club fungi
Water molds
Slime molds
Dimorphic fungi
Dimorphic fungi
34
Bacterial biofilms are important medically because:
Bacterial biofilms are important medically because:
They are resistant to antibiotics.
They can form dental plaque.
They may form on catheters
All are correct.
All are correct.
35
```
he basic requirements of PCR include:
The basic requirements of PCR include:
The DNA segment to be amplified
Two oligonucleotide primers
A heat stable DNA polymerase
All of the above
```
All of the above
36
80S ribosomes can be found in both prokaryotes and eukaryotes.
80S ribosomes can be found in both prokaryotes and eukaryotes.
True
False
False
37
In group translocation glucose becomes phosphorylated as it enters a cell.
In group translocation glucose becomes phosphorylated as it enters a cell.
True.
False.
True
38
Lactose fermenters produce red colonies on MacConkey agar.
Lactose fermenters produce red colonies on MacConkey agar.
True
False
True
39
The OF test differentiates bacteria on the basis of fermentative or oxidative metabolism of glucose.
The OF test differentiates bacteria on the basis of fermentative or oxidative metabolism of glucose.
True
False
T
40
Most Human pathogenic fungi are nonmotile
Most Human pathogenic fungi are nonmotile
False
True
True
41
Applied microbiology deals with important practical problems in
Applied microbiology deals with important practical problems in
medicine, agriculture, and industry.
medicine.
industry.
agriculture
medicine, agriculture, and industry.
42
________ was the first to describe microorganisms, while ________ was the first person to see bacteria.
________ was the first to describe microorganisms, while ________ was the first person to see bacteria.
Robert Koch / Antoni van Leeuwenhoek
Antoni van Leeuwenhoek / Robert Koch
Robert Hooke / Antoni van Leeuwenhoek
Antoni van Leeuwenhoek / Robert Hook
Robert Hooke / Antoni van Leeuwenhoek
43
The first documented description of a microorganism was of a ________ by ________.
The first documented description of a microorganism was of a ________ by ________.
bacterium / Ferdinand Cohn
fungus / Robert Koch
yeast / Martinus Beijerinck
mold / Robert Hooke
mold / Robert Hooke
44
Which of the following is NOT an accomplishment of Louis Pasteur?
Which of the following is NOT an accomplishment of Louis Pasteur?
developed heat sterilization techniques that involved the creation of a specialized swan-necked flask
developed enrichment culture techniques
developed the first rabies vaccine and treated thousands of individuals
determined that the alcohol-making process was mediated by microbial fermentation and thus refuted the theory of spontaneous generation
developed enrichment culture techniques
45
The theory of spontaneous generation was refuted by the work of
The theory of spontaneous generation was refuted by the work of
Robert Hooke.
Louis Pasteur.
Antoni van Leeuwenhoek.
Robert Koch.
Louis Pasteur.
46
Robert Koch contributed to the field of microbiology by being the first person to
Robert Koch contributed to the field of microbiology by being the first person to
develop the tuberculin test, formulate four postulates for definitively linking a specific microorganism to a specific disease, and use agar as a solidifying agent in growth media.
use agar as a solidifying agent in growth media.
formulate four postulates for definitively linking a specific microorganism to a specific disease.
develop the tuberculin test.
develop the tuberculin test, formulate four postulates for definitively linking a specific microorganism to a specific disease, and use agar as a solidifying agent in growth media.
47
________ are charged molecules that are partially responsible for the ________ charge of the gram-positive bacterial cell surface.
________ are charged molecules that are partially responsible for the ________ charge of the gram-positive bacterial cell surface.
Phospholipids / negative
Teichoic acids / negative
Peptide interbridges / neutral
Diaminopimelic acids / positive
Teichoic acids / negative
48
The peptide interbridge crosslinking between peptidoglycan layers is found ONLY in the cell walls of
The peptide interbridge crosslinking between peptidoglycan layers is found ONLY in the cell walls of
gram-positive Bacteria.
Archaea.
gram-negative Bacteria.
Eukarya
gram-positive Bacteria.
49
A student observed a stained specimen of bacteria using bright-field microscopy. At 100x magnification, there appeared to be only one cell in the field of view, but at 1000x it was clear that there were two cells close together. The ability to distinguish these two cells as separate entities is called __________.
Hints
Hint 1.
[[Microscopy]] Magnification alone is insufficient to see bacteria clearly.
A student observed a stained specimen of bacteria using bright-field microscopy. At 100x magnification, there appeared to be only one cell in the field of view, but at 1000x it was clear that there were two cells close together. The ability to distinguish these two cells as separate entities is called __________.
wavelength
resolution
magnification
cell division
resolution
50
You are given an electron micrograph of a bacterial cell. In the micrograph you can clearly see three thin layers of different densities surrounding the cell. Based on the micrograph, you can infer that this cell is ________ and would appear ________ after application of the Gram stain procedure.
You are given an electron micrograph of a bacterial cell. In the micrograph you can clearly see three thin layers of different densities surrounding the cell. Based on the micrograph, you can infer that this cell is ________ and would appear ________ after application of the Gram stain procedure.
gram-negative / purple
gram-positive / purple
gram-positive / pink
gram-negative / pink
gram-negative / pink
51
A bacterial cell is interpreted as gram-positive when it forms purple insoluble crystal violet-iodine complexes within the cell during the Gram stain.
A bacterial cell is interpreted as gram-positive when it forms purple insoluble crystal violet-iodine complexes within the cell during the Gram stain.
True
False
True
52
In gram-positive Bacteria, the cell walls are composed mainly of thick ________ layers.
In gram-positive Bacteria, the cell walls are composed mainly of thick ________ layers.
protein
peptidoglycan
lipopolysaccharides (LPS)
poly-β-hydroxybutryic acid (PHB)
peptidoglycan
53
The rigid layer that is present in the cell walls of Bacteria that is primarily responsible for the strength of the wall is known as
The rigid layer that is present in the cell walls of Bacteria that is primarily responsible for the strength of the wall is known as
cellulose.
pseudomurein.
peptidoglycan.
S-layer.
peptidoglycan
54
Bacteria stain as gram-positive or gram-negative because of differences in the cell
Bacteria stain as gram-positive or gram-negative because of differences in the cell
chromosome.
nucleus.
cytoplasm.
wall
wall
55
Teichoic acids are commonly found in gram-negative cell walls.
Teichoic acids are commonly found in gram-negative cell walls.
True
False
False
56
Specify why is it necessary to use stains to view microorganisms.
Hints
Hint 1.
[[staining]] Microorganisms are transparent. When you are using a bright-field microscope, what would the background look like when viewing specimens?
Specify why is it necessary to use stains to view microorganisms.
to increase the magnification of the organism and make the cells more visible
to increase the resolution of the organism and make the cells more visible
to kill the microorganism so it does not swim away
to increase the contrast and make the cells more visible
to increase the contrast and make the cells more visible
57
Electron microscopy has greater ________ than light microscopy, because the wavelengths of visible light are much larger than the wavelengths of electrons.
Electron microscopy has greater ________ than light microscopy, because the wavelengths of visible light are much larger than the wavelengths of electrons.
magnification
resolution
contrast
penetration
resolution
58
The use of the Gram stain in microbiology is important because it differentiates
The use of the Gram stain in microbiology is important because it differentiates
bacterial cells with different types of cell walls.
prokaryotic from eukaryotic cells.
Bacteria from Archaea.
archaeal cells with different types of metabolism.
bacterial cells with different types of cell walls.
59
The cytoplasmic membrane is termed "semi-permeable" because some substances, like water and alcohols, can pass freely through while others, like sugars, amino acids, and ions, cannot. What molecular characteristics largely determine whether or not a substance can pass through the membrane?
Hints
The cytoplasmic membrane is termed "semi-permeable" because some substances, like water and alcohols, can pass freely through while others, like sugars, amino acids, and ions, cannot. What molecular characteristics largely determine whether or not a substance can pass through the membrane?
size and hydrophobicity
usefulness to the cell
organic versus inorganic molecules
osmolarity
size and hydrophobicity
60
Aquaporins are
Aquaporins are
molecules that prevent water from crossing a membrane.
water transport proteins.
enzymes involved in the generation of water within cells.
cations bound to water molecules.
water transport proteins.
61
hich is/are a function(s) of the cytoplasmic membrane in prokaryotes?
Which is/are a function(s) of the cytoplasmic membrane in prokaryotes?
It serves as a permeability barrier, a docking station for proteins involved in bioenergetics reactions and transport, and a site for energy conservation.
It is an anchor for many proteins involved in bioenergetic reactions and transport.
It is a major site of energy conservation.
It functions as a permeability barrier.
It serves as a permeability barrier, a docking station for proteins involved in bioenergetics reactions and transport, and a site for energy conservation.
62
The lipopolysaccharide (LPS) layer is found ONLY in the cell walls of
The lipopolysaccharide (LPS) layer is found ONLY in the cell walls of
Eukarya.
gram-positive Bacteria.
gram-negative Bacteria.
Archaea
gram-negative Bacteria.
63
Cellular inclusions in prokaryotic cells serve to
Cellular inclusions in prokaryotic cells serve to
store energy rich compounds.
position cells in the appropriate environment for survival.
store energy rich compounds and position cells in the appropriate environment for survival.
protect DNA.
store energy rich compounds and position cells in the appropriate environment for survival.
64
In general, most cell inclusions function as energy reserves or as a reservoir of structural building blocks.
In general, most cell inclusions function as energy reserves or as a reservoir of structural building blocks.
True
False
True
65
Small acid-soluble proteins (SASPs) protect DNA from ultraviolet light and are found in high numbers within
Small acid-soluble proteins (SASPs) protect DNA from ultraviolet light and are found in high numbers within
endospores.
gram-negative Bacteria.
gram-positive Bacteria.
inclusion bodies.
endospores
66
What is the biological function of endospores?
What is the biological function of endospores?
They transport toxins.
They are bacterial reproductive structures.
They enable organisms to endure extremes of temperature, drying, and nutrient depletion.
Endospores can serve as reproductive structures, enable survival in harsh environments, and transport toxins
They enable organisms to endure extremes of temperature, drying, and nutrient depletion.
67
When does endospore formation commence?
When does endospore formation commence?
following bacterial death
when the bacterium is undergoing binary fission
when bacteria are dividing exponentially
when bacterial growth ceases due to limitation of an essential nutrient
when bacterial growth ceases due to limitation of an essential nutrient
68
Which of the following statements is FALSE?
Which of the following statements is FALSE?
Capsules and slime layers aid in attachment
Capsules and slime layers grant resistance to desiccation
Capsules and slime layers are responsible for dental plaque.
Capsules and slime layers assist phagocytosis
Capsules and slime layers assist phagocytosis
69
Which of the following statements is FALSE?
Which of the following statements is FALSE?
Fimbriae mediate DNA transfer
Fimbriae range from 3 -10 nm in diameter
Fimbriae are slender tubes of helically arranged protein subunits.
Fimbriae mediate attachment to surfaces.
Fimbriae mediate DNA transfer
70
In peritrichous flagellation, the flagella are _______ .
In peritrichous flagellation, the flagella are _______ .
Attached as a group at one or both ends of the cell.
Attached at one end of the cell.
Attached at both ends of the cell.
Attached at many locations across the entirety of the cell surface.
Attached at many locations across the entirety of the cell surface
71
Which list contains the correct components of a bacterial flagellum?
Hints
Hint 1.
[[flagella]] Flagella are found in some bacterial cells and are used for motility. If they are not formed correctly, the organism may be non-motile.
Which list contains the correct components of a bacterial flagellum?
filament, anchor, rotator
filament, hook, rotator
filament, anchor, basal body
filament, hook, basal body
filament, hook, basal body
72
Which of the following statements is FALSE?
Which of the following statements is FALSE?
In flagellar motion, the basal body acts as a motor.
Flagellar rotation generates ATP.
A flagellar protein subunit is flagellin.
The hook is the wider region at the base of the flagellum.
Flagellar rotation generates ATP.
73
```
Type IV pili are involved in
Type IV pili are involved in
pathogenesis.
attachment to surfaces, twitching motility, and pathogenesis.
twitching motility.
attachment of cells to surfaces.
```
attachment to surfaces, twitching motility, and pathogenesis.
74
e terms "run" and "tumble" are generally associated with
The terms "run" and "tumble" are generally associated with
clustering of certain rod-shaped bacteria.
chemotaxis.
eukaryotic cells.
nutrient transport.
chemotaxis.
75
Axial filaments found in spirochetes facilitate _______ .
Axial filaments found in spirochetes facilitate _______ .
Tumbling motility.
Cork-screw motility.
DNA transfer.
Cellular adhesion.
Cork-screw motility.
76
Chemotaxis is a sensory response affecting the rotational direction of the flagellar motor.
Chemotaxis is a sensory response affecting the rotational direction of the flagellar motor.
True
False
t
77
In general, swimming is performed with flagella, whereas gliding uses other cellular components such as pili.
In general, swimming is performed with flagella, whereas gliding uses other cellular components such as pili.
True
False
True
78
Which is an example of both a micronutrient and a trace element?
Which is an example of both a micronutrient and a trace element?
iron
arginine
inorganic phosphorous
vitamin B12
iron
79
Which element functions BOTH as an enzyme cofactor and as a stabilizer of ribosomes and nucleic acids?
Which element functions BOTH as an enzyme cofactor and as a stabilizer of ribosomes and nucleic acids?
magnesium
hydrogen
iron
zinc
magnesium
80
Trace elements are found in bacterial cells in very small amounts because they __________.
Hints
Trace elements are found in bacterial cells in very small amounts because they __________.
are toxic to the cell
are only found in limited quantities in the environment
are not essential to cell function
function only in a limited set of enzymes and cofactors
function only in a limited set of enzymes and cofactors
81
Based on the functional roles of phosphate in various microbial metabolisms, deduce which compounds phosphate exists as in microorganisms.
Based on the functional roles of phosphate in various microbial metabolisms, deduce which compounds phosphate exists as in microorganisms.
neither organic nor inorganic compounds
organic compounds
inorganic compounds
both organic and inorganic compounds
both organic and inorganic compounds
82
In aerobic respiration, the final electron acceptor is
In aerobic respiration, the final electron acceptor is
hydrogen.
ATP.
oxygen.
water.
oxygen
83
To ensure growth of a newly discovered bacterium with unknown nutritional requirements, it would be best to begin with a ________ medium rather than a ________ medium.
To ensure growth of a newly discovered bacterium with unknown nutritional requirements, it would be best to begin with a ________ medium rather than a ________ medium.
minimal / complex
selective / differential
selective / complex
complex / minimal
complex / minimal
84
Aseptic technique refers to
Aseptic technique refers to
the microbial inoculum placed into a test tube or onto a Petri plate.
a series of practices to avoid contamination.
the autoclave and other sterilizing procedures.
cleanliness in the laboratory.
a series of practices to avoid contamination.
85
A chemoorganotroph and a photoautotroph in the same environment would NOT compete for
A chemoorganotroph and a photoautotroph in the same environment would NOT compete for
nitrogen.
oxygen.
carbon.
carbon and oxygen.
carbon and oxygen.
86
A chemoorganotroph and a chemolithotroph in the same environment would NOT compete for
A chemoorganotroph and a chemolithotroph in the same environment would NOT compete for
oxygen.
nitrogen.
phosphorous.
carbon
carbon
87
For a carbon source, chemoorganotrophs generally use compounds such as
For a carbon source, chemoorganotrophs generally use compounds such as
nitrate and nitrite.
acetate, bicarbonate, and nitrate.
acetate, succinate, and glucose.
bicarbonate and carbon dioxide.
acetate, succinate, and glucose.
88
Which statement below demonstrates why the majority of organisms are heterotrophs?
Hints
Hint 1.
[[energy classes]] Organisms can be classified based on how they obtain both carbon and energy. All organisms require a great deal of carbon, but it can come from different sources. Some organisms conserve energy by the oxidation of either organic or inorganic compounds. Some organisms can convert light energy into chemical energy.
Which statement below demonstrates why the majority of organisms are heterotrophs?
The majority of organisms obtain their carbon from inorganic sources.
The majority of organisms conserve energy from inorganic sources.
The majority of organisms obtain their carbon from organic sources.
The majority of organisms conserve energy from inorganic sources and their carbon from organic sources.
The majority of organisms obtain their carbon from organic sources.
89
of the following would be used by a chemoorganotroph for energy?
Which of the following would be used by a chemoorganotroph for energy?
CO2
H+
C2H3O2-
H2
C2H3O2
90
If an oxidation reaction occurs
If an oxidation reaction occurs
a reduction reaction would not occur, because they are opposite reaction mechanisms. From the standpoint of the microorganism, in glycolysis the crucial product is
From the standpoint of the microorganism, in glycolysis the crucial product is
CO2; ATP is a waste product.
ethanol or lactate; ATP is a waste product.
ATP; the fermentation products are waste products.
not relevant because glycolysis is not a major pathway.
another oxidation reaction will occur for a complete reaction, because one oxidation event is considered a half reaction.
simultaneous reduction of a different compound will also occur, because electrons do not generally exist alone in solution.
a cell is undergoing aerobic respiration, because oxygen is being used.
simultaneous reduction of a different compound will also occur, because electrons do not generally exist alone in solution.
91
The Embden-Meyerhof-Parnas pathway is another name for
The Embden-Meyerhof-Parnas pathway is another name for
the citric acid cycle.
NADH production.
electron transport.
glycolysis
glycolysis.
92
Fermentation has a relatively low ATP yield compared to aerobic respiration because
Fermentation has a relatively low ATP yield compared to aerobic respiration because
more reducing equivalents are used for anaerobic catabolism.
oxidative phosphorylation yields a lot of ATP.
substrate-level phosphorylation yields a lot of ATP.
less ATP is consumed during the first stage of aerobic catabolism
oxidative phosphorylation yields a lot of ATP.
93
The net gain of ATP per molecule of glucose fermented is
The net gain of ATP per molecule of glucose fermented is
1.
4.
2.
8.
2
94
From the standpoint of the microorganism, in glycolysis the crucial product is
From the standpoint of the microorganism, in glycolysis the crucial product is
CO2; ATP is a waste product.
ethanol or lactate; ATP is a waste product.
ATP; the fermentation products are waste products.
not relevant because glycolysis is not a major pathway
ATP; the fermentation products are waste products.
95
In substrate-level phosphorylation, ATP storage is depleted during the steps in catabolism of the fermentable compounds.
In substrate-level phosphorylation, ATP storage is depleted during the steps in catabolism of the fermentable compounds.
True
False
F
96
How does the proton motive force lead to production of ATP?
How does the proton motive force lead to production of ATP?
ATPase requires one proton to make one ATP.
Oxidative phosphorylation of ADP by ATP synthase requires protons as cofactors in the reaction.
Protons must be pumped against a concentration gradient from outside of the cell into the cell to rotate the F0 subunit of ATPase for the F1 subunit to make ATP.
Translocation of three to four protons drives the F0 component of ATPase which in turn phosphorylates one ADP into ATP.
Translocation of three to four protons drives the F0 component of ATPase which in turn phosphorylates one ADP into ATP.
97
The rising of bread dough is the result of
The rising of bread dough is the result of
carbon dioxide produced by fermentation.
oxidative phosphorylation.
biotin production.
oxygen being released.
carbon dioxide produced by fermentation.
98
The terminating step of moving electrons onto oxygen releases additional ATP during aerobic metabolism not made during anaerobic growth.
The terminating step of moving electrons onto oxygen releases additional ATP during aerobic metabolism not made during anaerobic growth.
True
False
False
99
In electron transport systems, the electron carriers are membrane associated.
In electron transport systems, the electron carriers are membrane associated.
True
False
T
100
The proton motive force is most often generated by splitting of H2.
The proton motive force is most often generated by splitting of H2.
True
False
F
101
The net result of electron transport is the generation of a pH gradient and an electrochemical potential across the membrane.
The net result of electron transport is the generation of a pH gradient and an electrochemical potential across the membrane.
True
False
T
102
Which feature of anaerobic and aerobic respiration is different between the two catabolic strategies?
Which feature of anaerobic and aerobic respiration is different between the two catabolic strategies?
electron acceptor
use of proton motive force
use of electron transport
electron donor
electron acceptor
103
The two strands of the DNA double helix are held together by
The two strands of the DNA double helix are held together by
5' to 3' attraction.
peptide bonds between nucleotide bases.
codons.
hydrogen bonds between nucleotide bases.
hydrogen bonds between nucleotide bases.
104
Each adenine-thymine base pair has ________ hydrogen bonds, while each guanine-cytosine base pair has ________ hydrogen bonds.
Each adenine-thymine base pair has ________ hydrogen bonds, while each guanine-cytosine base pair has ________ hydrogen bonds.
three / two
two / three
two / one
four / three
two / three
105
Genetic information in the cell is carried by information molecules, including all EXCEPT which of the following?
Hints
Hint 1.
[[Genetic information]] Molecules can impart information based on their structures.
Genetic information in the cell is carried by information molecules, including all EXCEPT which of the following?
polypeptides
phospholipids
RNAs
DNAs
phospholipids
106
List the steps of the central dogma of molecular biology in the correct order.
Hints
Hint 1.
[[central dogma]] The central dogma describes how information flows in all cells. This is a universal truth for how genes are expressed in all living cells.
List the steps of the central dogma of molecular biology in the correct order.
RNA → DNA → protein
DNA → protein → RNA
DNA → RNA → protein
protein → RNA → DNA
DNA → RNA → protein
107
Supercoiling is important for DNA structure, because
Supercoiling is important for DNA structure, because
it condenses the DNA so that it can fit inside the cell.
it prevents RNA from pairing with DNA in the double helix.
it holds together the antiparallel strands of DNA in the double helix.
it provides energy for transcription.
it condenses the DNA so that it can fit inside the cell.
108
AT-rich DNA will denature/melt
AT-rich DNA will denature/melt
at a lower temperature than GC-rich DNA.
in accordance with the animal or plant from which it was taken.
usually at the same temperature as GC-rich DNA, with some minor variations.
at a higher temperature than GC-rich DNA.
at a lower temperature than GC-rich DNA.
109
complementary base pairing of DNA, adenine pairs with ________ (or ________ in RNA) and cytosine always pairs with ________.
In complementary base pairing of DNA, adenine pairs with ________ (or ________ in RNA) and cytosine always pairs with ________.
thymine / guanine / uracil
guanine / uracil / thymine
thymine / uracil / guanine
uracil / thymine / guanine
thymine / uracil / guanine
110
A plasmid differs from the bacterial chromosome in that it is __________.
Hints
Hint 1.
[[Plasmid Structure]] Plasmids are genetic elements found in most bacteria, and rarely in eukaryotes.
A plasmid differs from the bacterial chromosome in that it is __________.
always found as a single copy of DNA in a cell
double-stranded
significantly smaller
circular
significantly smaller
111
Plasmids function in bacterial cells to __________.
Hints
Hint 1.
[[Plasmid function]] Plasmids add important functions to some bacterial cells, affecting survival and pathogenesis.
Plasmids function in bacterial cells to __________.
confer to a cell additional genetic traits that are needed only under certain circumstances
transfer certain genes to other parts of the cell temporarily
transfer genes to other locations within the genome
infect cells in order to replicate their DNA
confer to a cell additional genetic traits that are needed only under certain circumstances
112
Which statement best describes an operon?
Hints
Hint 1.
[[prokaryotic DNA]] A major difference between eukaryotic and prokaryotic organisms is the way the DNA is organized. There are no introns or exons present in prokaryotic DNA.
Which statement best describes an operon?
several genes, next to each other in eukaryotic DNA, that are transcribed as a single piece of mRNA
several genes, next to each other in prokaryotic DNA, that are transcribed as a single piece of mRNA
several genes, at different locations in prokaryotic DNA, which are transcribed as a single piece of mRNA
a single gene in prokaryotic DNA that is transcribed as a single piece of mRNA
several genes, next to each other in prokaryotic DNA, that are transcribed as a single piece of mRNA
113
The function of the DNA polymerase is to catalyze
The function of the DNA polymerase is to catalyze
the formation of RNA primers.
the addition of ribonucleotides.
hydrogen bonding between complementary base pairs.
the addition of deoxynucleotides.
the addition of deoxynucleotides.
114
DNA replication always proceeds in only one direction because the ________ of the incoming nucleotide is attached to the free ________ of the growing DNA strand.
DNA replication always proceeds in only one direction because the ________ of the incoming nucleotide is attached to the free ________ of the growing DNA strand.
5'-phosphate / 3'-hydroxyl
5'-deoxyribose / 3'-base
3'-phosphate / 5'-hydroxyl
3'-base / 5'-deoxyribose
5'-phosphate / 3'-hydroxyl
| F
115
The formation of new DNA does NOT require energy.
The formation of new DNA does NOT require energy.
True
False
F
