Microbial Metabolism MCQs : This section focuses on the "Microbial Metabolism". These Multiple Choice Questions (MCQs) should be practiced to improve the Microbial Metabolism skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
During the carboxylation phase of the Calvin cycle, CO2 combines with
A. ribulose 1,5 - bisphosphate
B. phosphoglyceraldehyde
C. pyruvic acid
D. oxaloacetic acid
Question 2
Which of the following groups contain(s) many unique coenzymes, such as coenzyme M and coenzyme F420?
A. Sulfate-reducing bacteria
B. Methanotrophs (methane-oxidizing microbes)
C. Methanogens (methane-producing microbes)
D. Acetogens (acetigens; acetate-producing microbes)
Question 3
In the passive diffusion, solute molecules cross the membrane as a result of
A. concentration difference
B. pressure difference
C. ionic difference
D. All of the above
Question 4
In an oxygenic photosynthesis, the green and the purple bacteria do not use which of the following one as an electron source?
A. H2O
B. H2
C. H2S
D. S (elemental sulphur)
Question 5
Radioisotopes are frequently used in the study of cells. Assume a culture of E. coli is grown in a culture medium containing radioactive phosphorous. At the end of 48 hours, it is expected to find the radioactive label located in
A. enzymes
B. RNA
C. phospholipids
D. All of the above
Question 6
Assimilatory sulfate reduction involves the nucleotide __________ during the incorporation of H2S in the production of __________ .
A. ATP; methionine
B. ATP; cytosine
C. UTP; cytosine
D. GTP; cytosine
Question 7
The chlorophyll molecules used by eucaryotes and cyanobacteria absorb radiant energy in the____________portion(s) of the visible spectrum.
A. red
B. green
C. red and blue
D. green and ultraviolet
Question 8
In aerobic respiration, the terminal electron acceptor is
A. oxygen
B. nitrogen
C. hydrogen
D. nitrate
Question 9
Which of the following statement is correct?
A. Phosphate repression can not be eliminated by optimization of nutrient medium, deregulated medium must be used as production strains
B. Phosphate repression can be eliminated by optimization of nutrient medium, deregulated medium must be used as production strains
C. Phosphate repression can be eliminated by optimization of nutrient medium, regulated medium must be used as production strains
D. Phosphate repression can not be eliminated by optimization of nutrient medium, regulated medium must be used as production strains
Question 10
The acquisition energy by glucose fermentation requires
A. substrate-level phosphorylation
B. electron transport of electrons from NADH
C. long-chain fatty acid oxidation
D. the enzyme formic-hydrogen lyase
Question 11
High energy transfer compounds are capable of
A. accepting large amounts of free energy
B. transferring large amounts of free energy
C. measuring free energy
D. None of these
Question 12
Dolichol phosphate is
A. a complex lipid involved in docking vesicles with the plasma membrane
B. the anchor on which sugars assemble before transfer to proteins
C. a chaperone used in protein folding
D. a product of phospholipase C activation
Question 13
The reactions of the cell that are carried out for capturing energy are called
A. catabolism
B. metabolism
C. anabolism
D. activation energy
Question 14
In establishing proton gradient for chemiosmotic ATP generation by aerobic respiration the terminal electron acceptor is
A. nitrate
B. oxygen
C. sulfate
D. CO2
Question 15
If ΔG of a chemical reaction is positive in value and keq is less than 1 then the chemical reaction will
A. proceed in reverse direction
B. proceeed in forward direction
C. not take place in any of the direction
D. None of these
Question 16
The reaction, where small precursor molecules are assembled into larger organic molecules is referred as
A. anabolism
B. catabolism
C. metabolism
D. any of these
Question 17
Which of the following nucleoside diphosphates is used most often in carbohydrate anabolism?
A. Uridine diphosphate
B. Adenosine diphosphate
C. Guanine diphosphate
D. Thymine diphosphate
Question 18
DAHP synthetase catalyzes the condensation of
A. erythrose-4-phosphate
B. phosphoenol pyruvate
C. Both A and B
D. phenylalanine
Question 19
Phosphate is considered to restrict the induction of
A. primary metabolites
B. secondary metabolites
C. Both A and B
D. None of these
Question 20
Free energy change (ΔG) of a reaction is referred as the amount of energy
A. liberated during reaction
B. taken up during reaction
C. liberated or taken up during reaction
D. None of these
Question 21
Which of the following does not produce oxygen as a product of photosynthesis?
A. Oak trees
B. Purple sulfur bacteria
C. Cyanobacteria
D. Phytoplankton
Question 22
When acetate is the sole source of carbon for some microorganisms, the cycle which is used, is called
A. pentose phosphate pathway
B. glycolyic pathway
C. glyoxylate pathway
D. oxaloacetate pathway
Question 23
Hexose monophosphate pathway is also known as
A. phosphogluconate pathway
B. oxaloacetate pathway
C. malate pathway
D. fumerate pathway
Question 24
If radioactive bicarbonate was supplied to bacterial cells, which were actively synthesizing fatty acids, it is expected to find the bulk of the radioactivity in
A. cellular bicarbonate
B. the fatty acids
C. the cytoplasmic membrane
D. nucleic acids
Question 25
Standard free energy change (ΔG) can be expressed as
A. ΔG° = -RTlnkeq
B. ΔG° = RTlnkeq
C. ΔG° = R/Tlnkeq
D. ΔG° = -RT/lnkeq
Question 26
Aerobic catabolism of glucose yields how much energy (ATP synthesized) relative to glucose fermentation?
A. Slightly less
B. About the same
C. Twice as much
D. More than 10 times as much
Question 27
Anoxygenic photosynthetic bacteria oxidize
A. water
B. oxgyen
C. sulfide
D. ammonia
Question 28
As the electron flow through the chains, much of their free energy is conserved in the form of ATP. This process is called
A. oxidative phosphorylation
B. electromotive potential
C. dehydrogenations
D. none of these
Question 29
ATPase
A. synthesizes ATP, coupled to transfer of extracellular protons into the cell
B. extrudes protons from the cell coupled to the hydrolysis of ATP to ADP
C. is the enzyme that incorporates ATP into messenger RNA
D. carries out each of the reactions indicated in (a) and (b)
Question 30
Bacteriochlorophyll differs from chlorophyll in what way?
A. The chelated metal in bacteriochlorophyll is not Mg
B. There are chemical differences between the two chlorophyll in their side (R) groups
C. They have different absorption spectra
D. Both (b) and (c)
Question 31
DAHP synthetase catalyzes the condensation of
A. erythrose-4-phosphate
B. phosphoenol pyruvate
C. both (a) and (b)
D. phenylalanine
Question 32
Digestive reactions where large molecules are broken down into smaller ones are referred as
A. anabolism
B. catabolism
C. metabolism
D. biosynthesis
Question 33
Entner - Doudoroff pathway is not found in
A. aerobic prokaryotes
B. anaerobic prokaryotes
C. Both (a) and (b)
D. eukaryotes
Question 34
Entner-Doudoroff pathway is found in
A. aerobic prokaryotes
B. anaerobic prokaryotes
C. both (a) and (b)
D. aerobic eukaryotes
Question 35
For each glucose molecule broken down, there are______________number of reduced coenzymes to be oxidized.
A. 12
B. 8
C. 6
D. 4
Question 36
High energy transfer compounds are capable of
A. accepting large amounts of free energy
B. transferring large amounts of free energy
C. measuring free energy
D. none of the above
Question 37
If ΔG of a chemical reaction has a negative value, the reaction
A. releases energy
B. requires energy
C. both (a) and (b)
D. none of these
Question 38
If ΔG of a chemical reaction is positive in value and keq is less than 1 then the chemical reaction will
A. proceed in reverse direction
B. proceeed in forward direction
C. not take place in any of the direction
D. none of these
Question 39
In order to get inorganic phosphorous into organic compounds, the phosphate ion is incorporated via
A. substrate level phosphorylation
B. oxidative phosphorylation
C. both (a) and (b)
D. DNA
Question 40
In the passive diffusion, solute molecules cross the membrane as a result of
A. concentration difference
B. pressure difference
C. ionic difference
D. all of these
Question 41
Incorporation of atmospheric N2to NH4+ occurs via the process of
A. assimilatory nitrate reduction
B. transamination
C. deamination
D. nitrogen fixation
Question 42
Most of the energy in aerobic respiration of glucose is captured by
A. substrate-level phosphorylation
B. electron transport of electrons from NADH
C. long-chain fatty acid oxidation
D. the enzyme formic-hydrogen lyase
Question 43
Nitrogen fixation is a process that requires
A. energy
B. an anaerobic environment
C. both (a) and (b)
D. an aerobic environment
Question 44
Phosphate deregulated mutants are
A. less sensitive to phosphate regulation
B. moderately sensitive to phosphate regulation
C. highly sensitive to phosphate regulation
D. none of these
Question 45
Phosphate is considered to restrict the induction of
A. primary metabolites
B. secondary metabolites
C. both (a) and (b)
D. none of these
Question 46
Phosphate regulation has been observed in the production of
A. alkaloids
B. antibiotics
C. gibberelins
D. all of these
Question 47
Radioisotopes are frequently used in the study of cells. Assume a culture of E. coli is grown in a culture medium containing radioactive phosphorous. At the end of 48 hours, it is expected to find the radioactive label located in
A. enzymes
B. RNA
C. phospholipids
D. all of these
Question 48
Radioisotopes are frequently used in the study of cells. Assume a culture of E. coli is grown in a culture medium containing radioactive sulphur. At the end of 48 hours, it is expected to find the radioactive label located in
A. DNA
B. enzymes
C. RNA
D. all of these
Question 49
TCA cycle functions in
A. catabolic reactions
B. anabolic reactions
C. amphibolic reactions
D. none of these
Question 50
The bacteriochlorophylls used by the anoxygenic bacteria have absorbance maxima located in the_____portion(s) of the spectrum.
A. green
B. blue
C. ultraviolet
D. infrared
Question 51
The catabolic reaction, pentose-phosphate exists in
A. prokaryotic cells
B. eukaryotic cells
C. prokaryotic and eukaryotic cells both
D. none of these
Question 52
The glyoxylate cycle is used by some microorganisms when___________ is the sole carbon source.
A. acetate
B. nitrate
C. carbon dioxide
D. all of these
Question 53
The major route for incorporation of ammonia (NH4+) into organic compounds is via
A. reduction of pyruvate or alpha-ketoglutarate by enzymes
B. atmospheric nitrogen fixation
C. oxidation of pyruvate
D. all of these
Question 54
The mechanism of passive or facilitated diffusion require
A. metabolic energy
B. concentration of solute against an electrochemical gradient
C. accumulation of solute against an electrochemical gradient
D. accumulation or concentration of solute against an electrochemical gradient
Question 55
The phosphate inhibition in the clavine formation with Claviceps SD58, can be counteracted by the addition of
A. alanine
B. methionine
C. tryptophan
D. lysine
Question 56
The relationship between an oxidation-reduction potential difference and the standard free energy change is (where n is the number of moles of electron transferred, F= Faraday's constant and E°= standard oxidation-reduction potential difference)
A. ΔG° = -nFE°
B. ΔG° = nFE°
C. ΔG° = -nFlnE°
D. ΔG° = nFlnE°
Question 57
The role of bacteriophyll in an oxygenic photosynthesis is to
A. reduce ferridoxin directly
B. reduce NADP directly
C. use light energy to energize an electron
D. transfer electrons to an intermediate in the sulfide oxidation pathway
Question 58
The specific enzyme/(s) of the glyoxylate cycle is/are
A. isocitrate lyase
B. malate synthase
C. both (a) and (b)
D. anaplerotic
Question 59
Which of the following catalyze liberation of orthophosphate from organic P compounds and inorganic pyrophosphate ?
A. Alkaline phosphates
B. Oxidoreductase
C. Protease
D. Hydrogenase
Question 60
Which of the following is responsible for phosphate solubilization?
A. Streptococcus
B. Streptomyces
C. Bacillus
D. Clostridium
Question 61
Which of the following(s) is/are the products of the light reactions of photosynthesis?
A. ATP only
B. NADPH only
C. ATP and O2 only
D. ATP, NADPH, and O2