Explore topic-wise MCQs in Microbiology.

This section includes 71 Mcqs, each offering curated multiple-choice questions to sharpen your Microbiology knowledge and support exam preparation. Choose a topic below to get started.

51.

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
Answer» B. the fatty acids
52.

If G 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
Answer» B. requires energy
53.

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
Answer» E.
54.

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. G = -nFE
B. G = nFE
C. G = -nFlnE
D. G = nFlnE
Answer» B. G = nFE
55.

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)
Answer» E.
56.

The catabolic reaction, pentose-phosphate exists in

A. prokaryotic cells
B. eukaryotic cells
C. prokaryotic and eukaryotic cells both
D. none of these
Answer» D. none of these
57.

Entner - Doudoroff pathway is not found in

A. aerobic prokaryotes
B. anaerobic prokaryotes
C. Both (a) and (b)
D. eukaryotes
Answer» E.
58.

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
Answer» E.
59.

Phosphate is considered to restrict the induction of

A. primary metabolites
B. secondary metabolites
C. both (a) and (b)
D. none of these
Answer» C. both (a) and (b)
60.

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
Answer» C. RNA
61.

Entner-Doudoroff pathway is found in

A. aerobic prokaryotes
B. anaerobic prokaryotes
C. both (a) and (b)
D. aerobic eukaryotes
Answer» D. aerobic eukaryotes
62.

TCA cycle functions in

A. catabolic reactions
B. anabolic reactions
C. amphibolic reactions
D. none of these
Answer» D. none of these
63.

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
Answer» B. pressure difference
64.

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
Answer» C. a chaperone used in protein folding
65.

Which of the following does not produce oxygen as a product of photosynthesis?

A. Oak trees
B. Purple sulfur bacteria
C. Cyanobacteria
D. Phytoplankton
Answer» C. Cyanobacteria
66.

Free energy change ( G) 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
Answer» D. none of these
67.

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
Answer» B. Adenosine diphosphate
68.

Incorporation of atmospheric N2to NH4+ occurs via the process of

A. assimilatory nitrate reduction
B. transamination
C. deamination
D. nitrogen fixation
Answer» E.
69.

Phosphate regulation has been observed in the production of

A. alkaloids
B. antibiotics
C. gibberelins
D. all of these
Answer» E.
70.

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
Answer» B. electron transport of electrons from NADH
71.

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
Answer» D. oxaloacetate pathway