Microbiology Quiz

Question 1

Which media would turn pink with lactose fermentation?

Accepted Answer

MacConkey

Question 2

What causes bubbling in a positive catalase test?

Accepted Answer

Hydrogen peroxide decomposes into water and oxygen

Question 3

Which of the following is used in antimicrobial sensitivity testing?

Accepted Answer

Mueller-Hinton agar

Question 4

Which of the following is a facultative anaerobe that forms pink colonies on MacConkey agar?

Accepted Answer

Escherichia coli

Question 5

Yeasts reproduce by budding.

Accepted Answer

True

Question 6

What differentiates Clostridium perfringens from other Clostridium spp.?

Accepted Answer

It has a capsule but does not produce spores

Question 7

Brownian motion indicates true bacterial motility.

Accepted Answer

False

Question 8

Ziehl-Neelsen stain is used to visualize Cryptosporidium and Nocardia species.

Accepted Answer

True

Question 9

Which dimorphic fungus appears as spherules filled with endospores in tissues?

Accepted Answer

Histoplasma capsulatum, Sporothrix schenckii

Question 10

Bacterial spores are produced by gram-negative bacteria.

Accepted Answer

False

Question 11

Gram-positive organisms have thinner cell walls and appear pink after staining

Accepted Answer

False

Question 12

Gram-positive bacteria appear ______ under the microscope after staining.

Accepted Answer

Purple

Question 13

Which statement about virus envelopes is correct?

Accepted Answer

Derived from host cell membrane

Question 14

Salmonella spp. are lactose fermenters and appear pink on MAC agar.

Accepted Answer

False

Question 15

What gram-negative bacillus smells fruity on culture plates?

Accepted Answer

Pseudomonas aeruginosa

Question 16

Which fungal structure is a thick-walled, resting spore?

Accepted Answer

Chlamydospore

Question 17

Which fungal structure is used in asexual reproduction and appears as a unicellular spore?

Accepted Answer

Microconidia

Question 18

Which of the following is zoonotic?

Accepted Answer

Both A and C

Question 19

Which fungal organism appears as “peanut or footprint-shaped” cells in ear cytology?

Accepted Answer

Malassezia pachydermatis

Question 20

Coccidioides immitis is commonly found in moist forest environments.

Accepted Answer

False

Question 21

Which combination is correct regarding media type and its purpose?

Accepted Answer

Motility media – detects flagella function based on diffusion

Question 22

Which of these is associated with "snuffles" in rabbits?

Accepted Answer

Pasteurella multocida

Question 23

Clostridium perfringens produces spores.

Accepted Answer

False

Question 24

What is the primary lesion site for Blastomyces dermatitidis?

Accepted Answer

Lungs

Question 25

Which pathogen is coagulase-positive?

Accepted Answer

Staphylococcus aureus

Question 26

Which statement about Bacillus anthracis is true?

Accepted Answer

It forms a central spore and is non-motile

Question 27

Actinomyces bovis is found in normal oral flora and causes “lumpy jaw” in cattle.

Accepted Answer

True

Question 28

What agar is used to differentiate hemolytic patterns?

Accepted Answer

Blood Agar Plate (BAP)

Question 29

What stain is used to identify fungal structures microscopically?

Accepted Answer

Lactophenol cotton blue

Question 30

Viruses require a host cell to replicate.

Accepted Answer

True

Question 31

Klebsiella pneumoniae is motile and lacks a capsule.

Accepted Answer

False

Question 32

Which dimorphic fungus is often transmitted via rose thorns and causes lymphatic nodules?

Accepted Answer

Sporothrix schenckii

Question 33

Motile bacteria will only grow along the stab line in motility media.

Accepted Answer

False

Question 34

Which of the following is a reportable zoonotic pathogen?

Accepted Answer

Salmonella spp.

Question 35

What is a prion composed of?

Accepted Answer

Protein only

Question 36

Which of the following is the smallest microorganism?

Accepted Answer

Virus

Question 37

Which viral structure helps with host cell attachment and red blood cell agglutination?

Accepted Answer

Spikes

Question 38

Staphylococcus epidermidis is a coagulase-negative, non-pathogenic species.

Accepted Answer

True

Question 39

Which fungal infection is commonly referred to as ringworm?

Accepted Answer

Dermatophytosis

Question 40

Which of the following is a key characteristic of Corynebacterium pseudotuberculosis?

Accepted Answer

Causes “caseous lymphadenitis” in sheep

Question 41

Which organism is the common cause of “Lumpy Jaw” in cattle?

Accepted Answer

Actinomyces bovis

Question 42

What is the correct order of reagents in a Gram stain?

Accepted Answer

Crystal Violet, Iodine, Decolorizer, Safranin

Question 43

Which of the following organisms is a lactose fermenter on MacConkey agar?

Accepted Answer

Klebsiella pneumoniae

Question 44

Which of the following pathogens is acid-fast positive and poorly stained by Gram stain?

Accepted Answer

Mycobacterium bovis

Question 45

Which virus has a helical shape?

Accepted Answer

Rabies virus

Question 46

Prions contain DNA but lack a protein coat.

Accepted Answer

False

Question 47

Why is the McFarland standard used in indirect sensitivity testing?

Accepted Answer

To ensure a standardized bacterial concentration

Question 48

What is the correct way to write a bacterial species name?

Accepted Answer

Escherichia coli

Question 49

What shape are cocci bacteria?

Accepted Answer

Spherical

Question 50

What is the correct interpretation if a catalase test bubbles when using colonies from blood agar?

Accepted Answer

False positive due to blood contamination

Question 51

Which gram-negative bacillus causes kennel cough?

Accepted Answer

Bordetella bronchiseptica

Question 52

What stain is used to identify acid-fast organisms like Mycobacterium?

Accepted Answer

Ziehl-Neelsen

Microbiology Quiz

Questions 52

Microbiology Quiz

Questions 52