Explore topic-wise MCQs in Microbiology.

This section includes 26 Mcqs, each offering curated multiple-choice questions to sharpen your Microbiology knowledge and support exam preparation. Choose a topic below to get started.

1.

White spot in meat is formed due to presence of

A. <i>P. expansum</i>
B. <i>Sporotrichum carnis</i>
C. both (a) and (b)
D. <i>P. oxalicum</i>
Answer» C. both (a) and (b)
2.

Colorless rots in eggs is caused by

A. <i>Pseudomonas alcaligenes</i>
B. <i>Pseudomonas fluorescens</i>
C. both (a) and (b)
D. none of these
Answer» B. <i>Pseudomonas fluorescens</i>
3.

The greening of sausage may appear as a green ring not far from the casing, a green core, or a green surface. The cause of greening is the production of hydrogen peroxide by

A. hetero-fermentative species
B. catalase negative bacteria
C. both (a) and (b)
D. none of these
Answer» D. none of these
4.

Iced, cut up poultry often develops a slime i.e. accompanied by an odor describe as tainted, acid, sour or dishraggy. This defect is chiefly by the species of

A. <i>Pseudomonas</i>
B. <i>Alcaligenes</i>
C. hetero-fermentative species
D. catalase negative bacteria
Answer» B. <i>Alcaligenes</i>
5.

Which of the following is recommended for the improvement in flavor during ageing of beef under controlled conditions?

A. <i>Thamnidium </i>
B. <i>Rhizopus</i>
C. <i>T. elegans</i>
D. <i>M. mucedo</i>
Answer» B. <i>Rhizopus</i>
6.

In storage atmospheres of high humidity variety of molds may cause

A. superficial fungal spoilage
B. bacterial spoilage
C. both (a) and (b)
D. none of these
Answer» B. bacterial spoilage
7.

Which of the following microorganism spoil poultry in polyethylene bags?

A. <i>Pseudomonas-achromobacter</i>
B. <i>Alcaligenes</i>
C. hetero-fermentative species
D. catalase negative bacteria
Answer» B. <i>Alcaligenes</i>
8.

Black spot in meat are produced mainly by

A. <i>Cladosporium</i>
B. <i>Thamnidium </i>
C. <i>Mucor </i>
D. <i>Rhizopus</i>
Answer» B. <i>Thamnidium </i>
9.

The spoilage of eggs by fungi goes through stages of mold growth that give the defects their names. Very early mold growth is termed

A. pin-spot molding
B. fungal rotting
C. superficial fungal spoilage
D. any of these
Answer» B. fungal rotting
10.

Lactic acid bacteria in meats may be responsible for

A. slime formation at the surface or within especially in presence of sucrose
B. production of green discoloration
C. souring
D. all of the above
Answer» E.
11.

Green rots in eggs is chiefly caused by

A. <i>Pseudomonas fluorescens </i>
B. <i>Micrococcus or Bacillus species</i>
C. <i>Molds or yeasts</i>
D. all of the above
Answer» B. <i>Micrococcus or Bacillus species</i>
12.

Black rots in eggs is most commonly caused by

A. <i>species of Proteus</i>
B. <i>species of Micrococcus or Bacillus</i>
C. molds or yeasts
D. all of these
Answer» B. <i>species of Micrococcus or Bacillus</i>
13.

Pink rots in eggs is caused by the strains of

A. <i>Pseudomonas</i>
B. <i>Pseudomonas fluorescens</i>
C. species of Micrococcus or Bacillus
D. none of the above
Answer» B. <i>Pseudomonas fluorescens</i>
14.

Beef hams are made spongy by species of

A. <i>Rhodotorula</i>
B. <i> Bacillus</i>
C. <i>Pseudomonas</i>
D. <i>red Bacillus</i>
Answer» C. <i>Pseudomonas</i>
15.

The red color of meat, called its bloom, may be changed to shades of green, brown or grey as a result of production of oxidizing compounds by bacteria. Which of the following species are reported to cause the greening of sausage?

A. <i>Lactobacillus</i>
B. <i> Leuconostoc</i>
C. Both (a) and (b)
D. <i>Pseudomonas </i>
Answer» D. <i>Pseudomonas </i>
16.

Which of the cause(s) has/have been suggested for the chill rings in sausage?

A. Oxidation
B. Production of organic acids or reducing substances by bacteria
C. Excessive water
D. all of the above
Answer» E.
17.

Yellow discolorations in meat are caused by bacteria with yellow pigments, usually species of

A. <i> Micrococcus</i>
B. <i>Flavobacterium </i>
C. both (a) and (b)
D. <i>Pseudomonas syncyanea</i>
Answer» D. <i>Pseudomonas syncyanea</i>
18.

Which of the following (s) is/are responsible for the green patches on the surface of meats under aerobic conditions?

A. <i>P. expansum</i>
B. <i>P. asperulum</i>
C. <i>P. oxalicum</i>
D. All of these
Answer» E.
19.

Which of the following microorganisms grow in beef at a temperature of 15 C and above?

A. <i> Micrococci</i>
B. <i>Pseudomonas</i>
C. Both (a) and (b)
D. <i>Lactobacillus</i>
Answer» D. <i>Lactobacillus</i>
20.

The growth of Streptomyces on straw or elsewhere near the egg may produce

A. musty or earthy flavors
B. hay odour
C. fishy flavor
D. cabbage-water flavor
Answer» B. hay odour
21.

Unopened, sliced bacon, packaged in material somewhat highly resistant to oxygen permeability, is spoiled mostly by

A. Lactobacilli
B. Micrococci
C. fecal Streptococci
D. molds
Answer» B. Micrococci
22.

The technique first described to determine the incipient spoilage in meat was

A. homogenate extract volume (HEV)
B. agar Plate Count (APC)
C. extract Release Volume (ERV)
D. none of the above
Answer» D. none of the above
23.

Which of the following is responsible for a musty or earthy flavor?

A. <i>Actinomycetes</i>
B. <i>Flavobacterium</i>
C. both (a) and (b)
D. <i>Pseudomonas syncyanea</i>
Answer» B. <i>Flavobacterium</i>
24.

Molds causing spoilage of eggs include species of

A. <i>Cladosporium</i>
B. <i>Mucor </i>
C. <i>Thamnidium</i>
D. all of these
Answer» E.
25.

More spoilage of eggs is caused by

A. bacteria than molds
B. molds than bacteria
C. synergistically
D. none of these
Answer» B. molds than bacteria
26.

Vacuum packaged meats are spoiled by

A. <i>B. thermosphacta</i>
B. <i>Lactobacilli </i>
C. Both (a) and (b)
D. none of these
Answer» D. none of these