MCQs MICROBIOLOGY: Bacteria Morphology

1.
Which of the following bacteria lack a cell wall and are therefore resistant to penicillin?

A. Cyanobacteria B. Mycoplasmas
C. Bdellovibrios D. Spirochetes
Answer & Explanation
Answer: Option B

2.
A cluster of polar flagella is called

A. lophotrichous B. amphitrichous
C. monotrichous D. petritrichous
Answer & Explanation
Answer: Option A

3.
Flagella move the cell by

A. many flagella beating in a synchronous, whip-like motion
B. an individual flagellum beating in a whip-like motion
C. spinning like a propeller
D. attaching to nearby particles and contracting
Answer & Explanation
Answer: Option C
3.
Flagella move the cell by

A. many flagella beating in a synchronous, whip-like motion
B. an individual flagellum beating in a whip-like motion
C. spinning like a propeller
D. attaching to nearby particles and contracting
Answer & Explanation
Answer: Option C

4.
The protein from which hook and filaments of flagella are composed of, is

A. keratin B. flagellin
C. gelatin D. casein
Answer & Explanation
Answer: Option B

5.
The cooci which mostly occur in single or pairs are

A. Streptococci
B. Diplococci
C. Tetracocci
D. None of these
Answer & Explanation
Answer: Option B

6.
Which of the following may contain fimbriae?

A. Gram-positive bacteria
B. Gram-negative bacteria
C. Both (a) and (b)
D. None of these
Answer & Explanation
Answer: Option B

7.
Peptidoglycan accounts for __________ of the dry weight of cell wall in many gram positive bacteria

A. 50% or more
B. About 10%
C. 11%+ 0.22%
D. About 20%
Answer & Explanation
Answer: Option A

8.
Bacteria having no flagella are unable to

A. move
B. reproduce
C. stick to tissue surfaces
D. grow in nutrient agar
Answer & Explanation
Answer: Option A

9.
Which of the following is true about cell wall of gram-positive bacteria?

A. It consists of multiple layers
B. It is thicker than that associated with gram-negative bacteria
C. It contains teichoic acids
D. All of these
Answer & Explanation
Answer: Option D

10.
The cell walls of many gram positive bacteria can be easily destroyed by the enzyme known as

A. lipase B. lysozyme
C. pectinase D. peroxidase
Answer & Explanation
Answer: Option B

11.
The cell wall of

A. gram-positive bacteria are thicker than gram-negative bacteria
B. gram-negative bacteria are thicker than gram-positive bacteria
C. both have same thickness but composition is different
D. none of these
Answer & Explanation
Answer: Option A

12.
Peptidoglycan is also known as

A. N-acetyl muramic acid
B. murein mucopeptide
C. N acetylglucosamine
D. mesodiaminopimetic acid
Answer & Explanation
Answer: Option B

13.
Genetic system is located in the prokaryotes in

A. nucleoid
B. chromatin
C. nuclear material
D. all of these
Answer & Explanation
Answer: Option D

14.
Which is most likely to be exposed on the surface of a gram-negative bacterium?

A. Pore protein (porin)
B. Protein involved in energy generation
C. Lipoteichoic acid
D. Phospholipids
Answer & Explanation
Answer: Option A

15.
The last step in synthesis of peptidoglycan is

A. attachment of a peptide to muramic acid
B. attaching two amino acids to form a cross-link
C. attachment of a portion of peptidoglycan to a membrane lipid
D. binding of penicillin to a membrane protein
Answer & Explanation
Answer: Option B

V
17.
The cocci which forms a bunch and irregular pattern are

A. Staphylococci B. diplococci
C. Tetracocci D. Streptococci
Answer & Explanation
Answer: Option A

18.
Chemotaxis is a phenomenon of

A. swimming away of bacteria
B. swimming towards a bacteria
C. swimming away or towards of bacteria in presence of chemical compound
D. none of the above
Answer & Explanation
Answer: Option C

19.
The structure responsible for motility of bacteria is

A. pilli B. flagella
C. sheath D. capsules
Answer & Explanation
Answer: Option B

20.
The next to last step in peptidoglycan biosynthesis is

A. synthesis of the NAM-peptide subunit
B. removal of the subunit from bactoprenol
C. linking the sugar of the disaccharide-peptide unit to the growing peptidoglycan chain
D. cross-linking the peptide side chains of peptidoglycan
Answer & Explanation
Answer: Option C

21.
The cocci which forms a chain is

A. Streptococci B. diplococci
C. Staphylococci D. Tetracocci
Answer & Explanation
Answer: Option A

22.
The arrangement, in which flagella are distributed all round the bacterial cell, is known as

A. lophotrichous B. amphitrichous
C. peritrichous D. monotrichous
Answer & Explanation
Answer: Option C

23.
Periplasm is

A. the area between the inner and outer membranes of gram-negative bacteria
B. the area between the inner and outer membranes of Gram-positive bacteria
C. the interior portion of mitochondria
D. the area outside the cell membrane that is influenced by the polymers
Answer & Explanation
Answer: Option A

24.
Which of the following has peptidoglycan as a major constituent of cell wall?

A. Gram-negative bacteria
B. Gram-positive bacteria
C. Fungi
D. None of these
Answer & Explanation
Answer: Option B

25.
The common word for bacteria which are helically curved rods is

A. cooci B. pleomorphic
C. bacillus D. spirilla
Answer & Explanation
Answer: Option D

26.
The bacteria deficient in cell wall is

A. Treponema
B. Mycoplasma
C. Staphylococcus
D. Klebsiella
Answer & Explanation
Answer: Option B

27.
Which of the following is not true about peptidoglycan?

A. It is a polymer consisting of N-acetyl glucosamine, N-acetyl muramic acid and amino acids (alanine, lysine, etc.)
B. It is present in prokaryotic cell wall
C. It occurs in the form of a bag shaped macro molecule surrounding the cytoplasm membrane
D. None of the above
Answer & Explanation
Answer: Option D

28.
The common word for bacteria which are spherical in shape is

A. cocci B. bacilli
C. spirilla D. pleomorphic
Answer & Explanation
Answer: Option A

29.
Single or clusters of flagella at both poles is known as

A. monotrichous
B. petritrichous
C. amphitrichous
D. none of these
Answer & Explanation
Answer: Option C

30.
Which of the following bacterial genera (that produces endospore) have medical importance?

A. Clostridium
B. Bacillus
C. Both (a) and (b)
D. None of these
Answer & Explanation
Answer: Option C

 

31.
Microcapsules are composed of

A. proteins
B. polysaccharides
C. lipids
D. all of these
Answer & Explanation
Answer: Option D

32.
Gram positive cells have a

A. second outer membrane that helps to retain the crystal violet stain
B. multiple layer of peptidoglycan that helps to retain the crystal violet stain
C. thick capsule that traps the crystal violet stain
D. periplasmic space that traps the crystal violet
Answer & Explanation
Answer: Option B

33.
The common word for bacteria which are straight rod in shape is

A. cooci B. bacilli
C. spirilla D. pleomorphic
Answer & Explanation
Answer: Option B

34.
A single polar flagella is known as

A. monotrichous
B. lophotrichous
C. amphitrichous
D. none of these
Answer & Explanation
Answer: Option A

36.
In eukaryotic cells, ribosomes are

A. 70S
B. 60S
C. 80S
D. Not specific
Answer & Explanation
Answer: Option C

37.
Porins are located in

A. the outer membrane of gram-negative bacteria
B. the peptidoglycan layer of gram-positive bacteria
C. the cytoplasmic membrane of both gram-negative and gram-positive bacteria
D. the periplasmic space of gram-negative bacteria
Answer & Explanation
Answer: Option A

38.
Which of the following is exposed on the outer surface of a gram-negative bacterium?

A. O-antigen of lipopolysaccharide (LPS)
B. Polysaccharide portion of lipoteichoic acid (LTA)
C. Braun lipoprotein
D. Electron transport system components
Answer & Explanation
Answer: Option A

39.
Which of the following does not contain protein?

A. Pili
B. Flagellum
C. Lipoteichoic acid
D. Porin
Answer & Explanation
Answer: Option C

V
41.
Chemically the capsule may be

A. polypeptide
B. polysaccharide
C. either (a) or (b)
D. none of these
Answer & Explanation
Answer: Option C

V
43.
The cell walls of Gram positive bacteria contain two modified sugar, viz. N- acetylgucosamine (NAG) and N- acetylmuramic acid (NAM). They are covalently linked by

A. α- 1,4-glycosidic bond
B. β-1,6-glycosidic bond
C. α- 1,6-glycosidic bond
D. β- 1,4-glycosidic bond
Answer & Explanation
Answer: Option D

44.
Which of the following organism has sterols in their cytoplasmic membrane?

A. Clostridum B. Proteus
C. Mycoplasma D. Bacillius
Answer & Explanation
Answer: Option C

45.
Name the component of flagellum.

A. Filament
B. Hook
C. Basal body
D. All of these
Answer & Explanation
Answer: Option D

46.
The location where the bacterial chromosome concentrates is called

A. nucleus B. nuclein
C. nucleoid D. nucleose
Answer & Explanation
Answer: Option C

47.
Which of the following is analogous to mesosomes of bacteria?

A. Mitochondria of eukaryotes
B. Golgi apparatus of eukaryotes
C. Lysosomes of eukaryotes
D. None of these
Answer & Explanation
Answer: Option A

Explanation:

48.
Which of the following has Chinese letter arrangement?

A. Bacillus anthracis
B. Mycobacterium tuberculosis
C. Clostridium tetani
D. Corynebacterium diphtheriae
Answer & Explanation
Answer: Option D

49.
The other name for peptidoglycan is

A. mucopeptide
B. murein
C. both (a) & (b)
D. none of these
Answer & Explanation
Answer: Option C

50.
Cyanobacteria have

A. a gram-positive cell wall
B. a gram-negative cell wall
C. Neither (a) nor (b)
D. No cell wall
Answer & Explanation
Answer: Option B

51.
In which of the following, lipo-polysaccharide is a major constituent of outer membrane of the cellwall?

A. Gram-positive bacteria
B. Gram-negative bacteria
C. Fungi
D. None of these
Answer & Explanation
Answer: Option B

52.
Which of the following structure(s) is /are external to cell wall?

A. Flagella
B. Stalks
C. Sheath
D. All of these
Answer & Explanation
Answer: Option D

53.
Which of the following may be most likely to be missing from a gram-positive bacterium?

A. Penicillin binding protein
B. Peptidoglycan
C. Lipopolysaccharide
D. Phospholipid bilayer membrane
Answer & Explanation
Answer: Option C