1.What is the significance of producing isolated colonies in bacterial identification?
A) It allows for the identification of mixed cultures
B) It ensures the purity of the culture for accurate identification
C) It increases the growth rate of bacteria
D) It enhances the color of bacterial colonies

B) It ensures the purity of the culture for accurate identification

1.Which of the following is a characteristic used to describe bacterial colonies?
A) Odor
B) Temperature
C) pH level
D) Light intensity

A) Odor

1.What does the term 'pure culture' refer to in microbiology?
A) A culture containing multiple bacterial species
B) A culture containing only one species or strain of bacteria
C) A culture with no bacterial growth
D) A culture with mixed bacterial and fungal growth

B) A culture containing only one species or strain of bacteria

1.What does the appearance of bacterial colonies depend on?
A) The temperature of the environment
B) The species or strain of bacteria and substances they produce
C) The amount of light exposure
D) The presence of other microorganisms

B) The species or strain of bacteria and substances they produce

What is the primary function of flagella in bacteria?
A) Reproduction
B) Motility
C) Nutrient absorption
D) Protection

B) Motility

Which flagellar arrangement describes a single flagellum at one pole of the cell?
A) Lophotrichous
B) Amphitrichous
C) Monotrichous
D) Peritrichous

C) Monotrichous

What is the main challenge of using transmission electron microscopy to observe flagella?
A) It is not accurate
B) It is costly and technically challenging
C) It does not provide clear images
D) It requires staining

B) It is costly and technically challenging

What is Brownian motion?
A) True motility of bacteria
B) Random movement of particles due to collisions with atoms or molecules
C) Movement caused by flagella
D) Movement caused by cilia

B) Random movement of particles due to collisions with atoms or molecules

What is the purpose of using a motility medium?
A) To stain the bacteria
B) To confirm true motility
C) To heat-fix the bacteria
D) To observe Brownian motion

B) To confirm true motility

What is the concentration of agar used in a semi-solid motility medium?
A) 0.5%
B) 1.0%
C) 1.5%
D) 2.0%

A) 0.5%

Why is triphenyltetrazolium chloride (TTC) added to the motility medium?
A) To stain the bacteria
B) To act as an electron acceptor and indicate bacterial presence
C) To solidify the medium
D) To provide nutrients

B) To act as an electron acceptor and indicate bacterial presence

What color does TTC turn when reduced by bacteria?
A) Blue
B) Green
C) Red
D) Yellow

C) Red

What is the purpose of using a concave slide in a wet-mount preparation?

A) To heat-fix the specimen
B) To stain the specimen
C) To observe motile organisms directly
D) To incubate the specimen

C) To observe motile organisms directly

What is the term for a cell covered in flagella?
A) Monotrichous
B) Lophotrichous
C) Amphitrichous
D) Peritrichous

D) Peritrichous

What is the term used to describe very small bacterial colonies?
A) Large
B) Medium
C) Small
D) Pinpoint

D) Pinpoint

Which tool is recommended for observing the general appearance of a typical colony?
A)Electron microscope
B)Dissecting scope
C)Magnifying glass
D)Fluorescent microscope

C) Magnifying glass

What characteristic describes the edge of a bacterial colony?
A)Form
B)Margin
C)Elevation
D)Opacity

B) Margin

How is the elevation of a bacterial colony observed?
A)From the top of the plate
B)From the side of the plate
C)Under a fluorescent light
D)Using a magnifying glass

B) From the side of the plate

What does it mean if a colony is described as opaque?
A)It allows all light to pass through
B)It allows most light to pass through
C)It blocks most of the light
D)It reflects light

C) It blocks most of the light

What indicates that bacteria produce an intracellular pigment?
A)The medium becomes colored
B)The colony becomes colored
C)The colony remains colorless
D)The colony becomes translucent

B) The colony becomes colored

What is the term for colonies that take on the color of the straw-colored
media?
A)Pigmented
B)Nonpigmented
C)Translucent
D)Opaque

B) Nonpigmented

Why should the plate be placed in an inverted position during incubation?
A) To prevent contamination
B) To enhance bacterial growth
C) To observe colony morphology
D) To prevent condensation from dripping onto the colonies

D) To prevent condensation from dripping onto the colonies

What causes microbial colonies to be colored?
A) The presence of intracellular pigments
B) The presence of extracellular pigments
C) Both intracellular and extracellular pigments
D) The shape of the colonies

C) Both intracellular and extracellular pigments

What happens to the media if the organism produces an extracellular pigment?
A) The media remains colorless
B) The media becomes colored
C) The media becomes opaque
D) The media becomes translucent

B) The media becomes colored

Which of the following describes the different degrees of opacity in microbial
colonies?
A) Transparent, translucent, opaque
B) Small, medium, large
C) Flat, raised, convex
D) Smooth, rough, wrinkled

A) Transparent, translucent, opaque

Why is it preferable to mark the bottom of the Petri dish rather than the top?
A) To prevent contamination
B) To ensure the markings are not erased during incubation
C) To make it easier to observe the colonies
D) To avoid confusion with other plates

B) To ensure the markings are not erased during incubation

Why must you flame the loop in between each set of streaks?
A) To sterilize the loop and prevent cross-contamination
B) To heat-fix the bacteria
C) To dry the loop
D) To cool the loop

A) To sterilize the loop and prevent cross-contamination

What is the common method used to isolate organisms in microbiology?
A) Pour plate method
B) Spread plate method
C) Streak plate procedure
D) Serial dilution

C) Streak plate procedure

Why should you “drag” organisms from the previous streak section for only part
of the streaking of the next section?
A) To ensure even distribution of organisms
B) To create a dilution gradient and isolate individual colonies
C) To prevent overgrowth of bacteria
D) To enhance bacterial motility

B) To create a dilution gradient and isolate individual colonies

What is the purpose of using a broth culture as inoculum in the streak plate
method?
A) To increase the nutrient content
B) To ensure a uniform distribution of bacteria
C) To simplify the inoculation process
D) To prevent contamination

B) To ensure a uniform distribution of bacteria

What is the recommended incubation temperature for the streak plate method?
A) 25°C
B) 30°C
C) 37°C
D) 42°C

C) 37°C

Why is it important to use sterile technique when obtaining organisms from broth
or solid medium?
A) To enhance bacterial growth
B) To prevent contamination
C) To increase the nutrient content
D) To simplify the inoculation process

B) To prevent contamination

What is the ideal characteristic of an antimicrobial drug?
A) It kills the harmful organism without damaging the host
B) It acts as a disinfectant
C) It is effective against all types of pathogens
D) It is inexpensive

A) It kills the harmful organism without damaging the host

38. Why might the susceptibility of a pathogen to a specific antibiotic change during
therapy?
A) Due to changes in the host's immune system
B) Due to the development of antibiotic resistance
C) Due to the presence of multiple pathogens
D) Due to the type of agar medium used

B) Due to the development of antibiotic resistance

39. What was the purpose of the earliest methods of utilizing agar media in the
1940s?
A) To identify bacterial species
B) To determine the minimum inhibitory concentration (MIC) of antimicrobial agents
C) To develop new antibiotics
D) To study bacterial growth patterns

B) To determine the minimum inhibitory concentration (MIC) of antimicrobial agents

40. What is the Kirby-Bauer method also known as?
A) Broth dilution method
B) Disk diffusion method
C) Agar dilution method
D) Tube dilution method

B) Disk diffusion method

41. What does a clear zone around a disk in the Kirby-Bauer method indicate?
A) The presence of bacterial growth
B) The absence of bacterial growth
C) The presence of fungal growth
D) The absence of fungal growth

B) The absence of bacterial growth

What factors determine the size of the zone of inhibition in the Kirby-Bauer
method?
A) The type of agar used and the incubation temperature
B) The relative susceptibility of the microbe and the diffusion rate of the chemical
C) The concentration of the inoculum and the type of Petri dish used
D) The duration of incubation and the type of antibiotic used

B) The relative susceptibility of the microbe and the diffusion rate of the chemical

What are the possible results reported in the Kirby-Bauer method?
A) Positive, negative, or neutral
B) Sensitive, intermediate, or resistant
C) High, medium, or low
D) Effective, ineffective, or partially effective

B) Sensitive, intermediate, or resistant

Why are antibiotics not effective against viruses?
A) Viruses are too small to be affected by antibiotics
B) Antibiotics target bacterial structures and functions, not viral ones
C) Viruses are resistant to all antimicrobial agents
D) Viruses do not cause infections
Exercise 6.6 UVGI (2-Day Lab)

B) Antibiotics target bacterial structures and functions, not viral ones

45. What type of radiation is ultraviolet radiation classified as?
A) Ionizing radiation
B) Non-ionizing radiation
C) Visible light
D) Infrared radiation

B) Non-ionizing radiation

46. What type of damage does ultraviolet radiation cause to DNA?
A) Breaks in the DNA strand
B) Formation of pyrimidine dimers
C) Deletion of nucleotides
D) Insertion of nucleotides

B) Formation of pyrimidine dimers

47. Which nitrogenous bases are typically involved in the formation of pyrimidine
dimers due to UV radiation?
A) Adenine and guanine
B) Cytosine and guanine
C) Thymine and cytosine
D) Thymine and thymine

D) Thymine and thymine

48. What is the wavelength range of UV-C radiation used in Ultraviolet Growth
Inhibition (UVGI)?
A) 100 to 280 nm
B) 280 to 315 nm
C) 315 to 400 nm
D) 400 to 700 nm

A) 100 to 280 nm

49. What is the primary effect of UV-C radiation on bacteria?
A) It enhances bacterial growth
B) It causes mutations or cell death
C) It increases bacterial motility
D) It promotes bacterial reproduction

B) It causes mutations or cell death

50. Why is UV-C radiation considered to have maximum germicidal effect?
A) It has the longest wavelength
B) It penetrates deeply into tissues
C) It has the shortest wavelength and highest energy
D) It is absorbed by water

C) It has the shortest wavelength and highest energy

What is the main application of Ultraviolet Growth Inhibition (UVGI)?
A) Enhancing plant growth8
B) Sterilizing medical instruments and surfaces
C) Promoting human health
D) Increasing food shelf life

B) Sterilizing medical instruments and surfaces

What is a potential health risk of exposure to UV-C radiation for humans?
A) Increased risk of skin cancer
B) Enhanced immune response
C) Improved vision
D) Reduced risk of infections

A) Increased risk of skin cancer

53. What is one way microorganisms adjust their environment to survive?
A) By increasing the oxygen levels
B) By changing the temperature or pH of the environment
C) By reducing the nutrient availability
D) By eliminating host resources

B) By changing the temperature or pH of the environment

54. What is a side effect of bacterial metabolism and infection?
A) Increased oxygen levels
B) Enhanced immune response
C) Disease
D) Reduced metabolic waste

C) Disease

55. What is the primary difference between Gram-positive and Gram-negative
bacteria?
A) Gram-positive bacteria have a thin layer of peptidoglycan
B) Gram-negative bacteria have a thick layer of peptidoglycan
C) Gram-positive bacteria have a thick layer of peptidoglycan within their cell wall
D) Gram-negative bacteria lack peptidoglycan

C) Gram-positive bacteria have a thick layer of peptidoglycan within their cell wall

56. What is the Enterotube II system specifically used for?
A. Identifying Gram-positive bacteria
B. Identifying gamma Proteobacteria
C. Identifying facultative anaerobes of the family Enterobacteriaceae
D. Identifying bacterial enzymes and fermentations

C) Identifying facultative anaerobes of the family Enterobacteriaceae

57. How do commercial rapid diagnostic kits, like the Enterotube II system, benefit
laboratory technicians?
A. They are more accurate than traditional methods
B. They save money, effort, and critical diagnostic time
C. They can identify over 200 species of bacteria
D. They are specific for Gram-positive organisms

B) They save money, effort, and critical diagnostic time

Which growth pattern is characterized by bacteria floating on the top of the broth due to a waxy cell wall or gas vacuole?
A. Sediment
B. Uniform fine turbidity
C. Pellicle
D. Flocculent

C) Pellicle

59. What can cause changes in the expected growth patterns of bacteria in broth?
A. The type of agar used
B. The genetic makeup of the bacteria
C. Differences in incubation conditions such as time, temperature, pH, and nutrient
composition
D. The method of inoculation

C) Differences in incubation conditions such as time, temperature, pH, and nutrient composition

60. What is the term for the growth pattern where bacteria form clumps or
aggregates throughout the broth?
A. Sediment
B. Uniform fine turbidity
C. Pellicle
D. Flocculent

D) Flocculent

61. Which factor is NOT mentioned as potentially altering bacterial growth patterns in
broth?
A. Incubation time and temperature
B. pH and nutrient composition
C. Nitrogen, oxygen, carbon dioxide, and light levels
D. The type of Petri dish used

D) The type of Petri dish used

62. What is the significance of colony morphology in identifying unknown bacteria?
A. It provides a definitive identification of the bacteria
B. It helps differentiate between bacteria based on their growth patterns
C. It indicates the genetic makeup of the bacteria
D. It shows the bacteria’s resistance to antibiotics

B) It helps differentiate between bacteria based on their growth patterns

63. What are the two purposes of the enzyme urease in bacteria?
A. Neutralizing acidic environments and providing nitrogen for protein synthesis
B. Neutralizing acidic environments and providing ammonia for DNA and RNA synthesis
C. Hydrolyzing urea to carbon dioxide and water
D. Producing acidic waste products and increasing pH

A) Neutralizing acidic environments and providing nitrogen for protein synthesis

64. Which of the following is NOT a component of Rustigian and Stuart’s Urea broth?
A. Urea
B. Phenol red
C. Dextrose
D. Yeast extract

C) Dextrose

What color change indicates a urease-positive organism in the urea broth?
A. Orange to yellow
B. Yellow to red
C. Orange to pink
D. Pink to orange

C) Orange to pink

66. What is the purpose of the Durham tube in the phenol red experiment?
A. To measure the pH of the medium
B. To collect gases formed as by-products of sugar fermentation
C. To provide nutrients for bacterial growth
D. To indicate the presence of acid production

B) To collect gases formed as by-products of sugar fermentation

67. What color change indicates acid production in the phenol red experiment?
A. Red to pink/fuchsia
B. Yellow or orange to red
C. Red to yellow or orange
D. Pink/fuchsia to red
Exercise 7.5

C) Red to yellow or orange

68. What is the primary purpose of Fluid Thioglycollate (FTG) medium?
A. To provide nutrients for bacterial growth
B. To determine whether a bacterium is an aerobe or an anaerobe
C. To sterilize bacterial cultures
D. To measure the pH of the medium

B) To determine whether a bacterium is an aerobe or an anaerobe

69. What role does resazurin play in the FTG medium?
A. It provides nutrients for bacterial growth
B. It acts as an indicator of oxidation-reduction
C. It retards the diffusion of oxygen into the medium
D. It sterilizes the medium

B) It acts as an indicator of oxidation-reduction

70. Where in the FTG medium would you expect to find obligate anaerobes growing?
A. At the top of the tube
B. In the middle of the tube
C. At the bottom of the tube
D. Throughout the tube

C) At the bottom of the tube

71. What is the function of catalase in bacteria?
A. To produce hydrogen peroxide
B. To neutralize hydrogen peroxide by degrading it into water and oxygen
C. To synthesize hydrogen peroxide
D. To produce free radicals

B) To neutralize hydrogen peroxide by degrading it into water and oxygen

Which of the following bacteria are catalase positive?
A. Streptococcal spp.
B. Enterococci
C. Staphylococcal spp.
D. All of the above

C) Staphylococcal spp.

73. What indicates a positive catalase test result?
A. No bubbles observed
B. Formation of bubbles
C. Change in color
D. Production of free radicals

B) Formation of bubbles

74. What is the role of cytochrome c oxidase in the electron transport chain (ETC)?
A. To donate electrons to oxygen to form water
B. To produce ATP directly
C. To transfer electrons to cytochromes
D. To accept electrons from oxygen

A) To donate electrons to oxygen to form water

75. Which reagent is used in the oxidase test to identify cytochrome c oxidase–positive
organisms?
A. Phenol red
B. Tetramethyl-p-phenylene diamine
C. Resazurin
D. Sodium thioglycollate

B) Tetramethyl-p-phenylene diamine

76. What color change indicates a positive result in the oxidase test?
A. No color change
B. Dark blue/purple
C. Red to yellow
D. Orange to pink

B) Dark blue/purple

77. What enzyme do Proteus and Providencia species produce that removes the amine
group from phenylalanine?
A. Phenylalanine decarboxylase
B. Phenylalanine deaminase
C. Urease
D. Catalase

B) Phenylalanine deaminase

78. What color change indicates a positive result for phenylalanine deaminase activity?
A. Yellow to red
B. Red to yellow
C. Yellow to green
D. Green to yellow

C) Yellow to green

What is the purpose of the 12% ferric chloride (FeCl3) reagent in the phenylalanine
deaminase test?
A. To provide nutrients for bacterial growth
B. To act as a pH indicator
C. To react with keto-acids like phenylpyruvic acid to produce a green color
D. To sterilize the medium

C) To react with keto-acids like phenylpyruvic acid to produce a green color

80. What is the role of lipase in bacteria?
A. To synthesize lipids
B. To hydrolyze lipids into smaller subunits
C. To transport lipids inside the cell
D. To produce ATP directly

B) To hydrolyze lipids into smaller subunits

81. What indicates lipolytic activity in a lipase-positive organism on tributyrin agar?
A. The agar turns red
B. A clearing or dark halo around the bacterial growth
C. The agar becomes more opaque
D. No change in the agar

B) A clearing or dark halo around the bacterial growth

82. Which of the following is NOT a component of the media used for testing lipolytic
activity?
A. Peptone
B. Beef extract
C. Tributyrin oil
D. Glucose

D) Glucose

83. What does SIM stand for in the context of microbiological testing?
A. Sulfur, indole, and motility
B. Sodium, iron, and motility
C. Sulfur, iron, and metabolism
D. Sodium, indole, and metabolism

A) Sulfur, indole, and motility

84. What is the purpose of sodium thiosulfate in SIM media?
A. To provide a source of protein
B. To act as a sulfur source
C. To adjust the pH of the medium
D. To serve as an iron-containing compound

B) To act as a sulfur source

85. Why is SIM medium considered a combination differential media?
A. It tests for multiple biochemical features specific to Enterobacteriaceae family
members
B. It contains multiple sources of protein
C. It can be used at different temperatures
D. It has a pH range of 7.1 to 7.4

A) It tests for multiple biochemical features specific to Enterobacteriaceae family members

What is the purpose of the MR-VP broth in glucose fermentation testing?
A. To provide a source of protein
B. To test for the pathway used to ferment glucose
C. To measure the pH of the medium
D. To detect the presence of ethanol

B. To test for the pathway used to ferment glucose

87. Which fermentation pathway is detected by the Voges-Proskauer test?
A. Mixed acid fermentation
B. Butanediol fermentation
C. Alcohol fermentation
D. Lactic acid fermentation

B. Butanediol fermentation

88. What is the pH range at which methyl red changes color to indicate a positive result
for mixed acid fermentation?
A. Below 4.5
B. Above 6.0
C. Between 4.5 and 6.0
D. Exactly at 7.0

A. Below 4.5

89. Which of the following is NOT a product of the mixed acid fermentation pathway?
A. Succinic acid
B. Formic acid
C. 2,3-butanediol
D. Ethanol

C. 2,3-butanediol

90. What does the Voges-Proskauer test detect in glucose fermentation?
A. The production of organic acids
B. The production of acetoin and 2,3-butanediol
C. The production of hydrogen gas
D. The production of carbon dioxide

B. The production of acetoin and 2,3-butanediol

91. What is the sole carbon source in Simmon’s citrate medium?
A. Ammonium salts
B. Sodium citrate
C. Peptides
D. Bromthymol blue

B. Sodium citrate

92. What color change indicates a positive result for citrate utilization in Simmon’s citrate
medium?
A. Green to yellow
B. Yellow to green

C. Green to blue
D. Blue to green

C. Green to blue

What compound is formed in the medium as a result of citrate hydrolysis and
subsequent reactions?
A. Sodium chloride
B. Sodium carbonate
C. Sodium hydroxide
D. Sodium bicarbonate

B. Sodium carbonate

94. What is the purpose of cooling the gelatin medium to below 25°C after incubation?
A. To solidify the gelatin if it is still present
B. To melt the gelatin
C. To activate the enzyme gelatinase
D. To increase the temperature of the medium

A. To solidify the gelatin if it is still present

95. What indicates a positive result for gelatinase activity in the gelatin medium?
A. The medium becomes solid after cooling
B. The medium remains liquid after cooling
C. The medium changes color
D. The medium produces gas bubbles

B. The medium remains liquid after cooling

96. What does the enzyme gelatinase hydrolyze gelatin into?
A. Glucose and fructose
B. Peptides and amino acids
C. Fatty acids and glycerol
D. Carbon dioxide and water

B. Peptides and amino acids

97. What are the two glucose polymers that make up a molecule of starch?
A. Amylose and cellulose
B. Amylopectin and cellulose
C. Amylose and amylopectin
D. Cellulose and glycogen

C. Amylose and amylopectin

98. What indicates a positive starch test when iodine is added to the medium?
A. A dark color (purple/brown) around the bacterial growth
B. A colorless (golden) halo around the bacterial growth
C. No change in color
D. A red color around the bacterial growth

A. A dark color (purple/brown) around bacterial growth

99. What is the role of the enzyme amylase in bacteria?
A. To synthesize starch from glucose
B. To hydrolyze starch into smaller molecules like dextrins, maltose, and glucose
C. To transport starch into the bacterial cell
D. To produce iodine

B. To hydrolyze starch into smaller molecules like dextrins, maltose, and glucose

How do nonmotile bacteria grow in the motility test medium?
A. They grow away from the stab line
B. They grow along the stab line
C. They grow throughout the medium
D. They do not grow in the medium

B. They grow along the stab line

101. What color change occurs in the motility test medium when triphenyltetrazolium
chloride (TTC) is reduced by bacterial metabolism?
A. Colorless to blue
B. Red to colorless
C. Colorless to red
D. Red to yellow

C. Colorless to red

102. What is the primary by-product of sucrose fermentation by Streptococcus species
in the oral cavity?
A. Dextran
B. Organic acid
C. Polysaccharides
D. Polypeptides

B. Organic acid

103. What role does dextran play in the formation of dental caries?
A. It neutralizes organic acids
B. It forms a biofilm that helps retain organic acids on the tooth surface
C. It acts as a nutrient for other bacteria
D. It dissolves tooth enamel directly

B. It forms a biofilm that helps retain organic acids on the tooth surface

104. Why is effective brushing and flossing important in preventing dental caries?
A. It removes the bacteria from the oral cavity
B. It neutralizes the organic acids produced by bacteria
C. It removes plaque, which contains the biofilm and bacteria
D. It increases the production of saliva

C. It removes plaque, which contains the biofilm and bacteria

105. What factors determine the specificity of normal microbial flora in different
locations within the body?
A. Oxygen concentration, pH, moisture, and types of secretions
B. Temperature, light, and nutrient availability
C. Presence of pathogens and immune response
D. Blood type and genetic makeup

A. Oxygen concentration, pH, moisture, and types of secretions

106. What indicates alpha hemolysis on blood agar plates (BAPs)?
A. A clearing of the medium around the colony
B. A greening of the plate around the colony
C. Black pinpoint colonies
D. No change in the medium

B. A greening of the plate around the colony

Which type of agar plate is used for the isolation and differentiation of
Staphylococci?
A. Blood agar plates (BAPs)
B. Chocolate agar plates
C. Tellurite agar plates
D. Mannitol salt agar plates

D. Mannitol salt agar plates

108. How are the four major classes of the phylum Protozoa distinguished?
A. By their color
B. By their locomotor or reproductive structures
C. By their size
D. By their habitat

B. By their locomotor or reproductive structures

109. What are the two primary forms of amoeba found in their host?
A. Spores and cysts
B. Trophozoites and spores
C. Trophozoites and cysts
D. Flagellates and ciliates

C. Trophozoites and cysts

110. Where are trophozoites usually found in the host?
A. In formed stools
B. In fresh diarrheal stools
C. In the bloodstream
D. In the respiratory tract

B. In fresh diarrheal stools

111. Which characteristic is diagnostic for the trophozoite of E. histolytica?
A. Presence of food vacuoles
B. Ingested red blood cells (RBCs)
C. Short and blunt pseudopodia
D. Eccentric nucleolus

B. Ingested red blood cells (RBCs)

112. How is the cyst of E. coli distinguished from that of E. histolytica?
A. Presence of a central glycogen vacuole
B. Presence of eight nuclei with short chromatoid bodies
C. Presence of a halo-like appearance around the nucleolus
D. Presence of large glycogen inclusions

B. Presence of eight nuclei with short chromatoid bodies

113. Which organism does not form cysts and has a trophozoite with one or two nuclei
arranged at opposite ends of the cell?
A. E. nana
B. I. butschlii
C. D. fragilis
D. E. hartmanni

C. D. fragilis

Which characteristic is unique to the trophozoite of C. mesnili?
A. Bilaterally symmetrical with two sucking disks
B. Pear-shaped with three anterior flagella, one in the cytosome
C. Oval in shape with an undulating membrane
D. Oval in shape with a smooth wall

B. Pear-shaped with three anterior flagella, one in the cytosome

115. How can the cyst of G. lamblia be described?
A. Lemon-shaped with a protrusion at the anterior end
B. Oval in shape with a smooth wall and granular cytoplasm
C. Pear-shaped with three anterior flagella
D. Oval to pear-shaped with an undulating membrane

B. Oval in shape with a smooth wall and granular cytoplasm

116. Which organism is found only as a feeding trophozoite and has no cyst stage?
A. C. mesnili
B. G. lamblia
C. T. hominis
D. E. histolytica

C. T. hominis

117. What are the two large groups of helminths?
A. Roundworms (nematodes) and flatworms (platyhelminthes)
B. Tapeworms (cestodes) and flukes (trematodes)
C. Nematodes and cestodes
D. Trematodes and nematodes

A. Roundworms (nematodes) and flatworms (platyhelminthes)

118. How are tapeworms (cestodes) different from flukes (trematodes)?
A. Tapeworms are cylindrical, while flukes are flattened
B. Tapeworms are segmented, while flukes are not segmented
C. Tapeworms are hermaphroditic, while flukes have two sexes
D. Tapeworms are short, while flukes are long

B. Tapeworms are segmented, while flukes are not segmented

119. What is a proglottid in the context of tapeworms?
A. The head of the worm
B. A segment containing male and female sexual organs
C. A hooklet used for attachment
D. A leaf-shaped structure

B. A segment containing male and female sexual organs

120. What are the three different organisms in the Fungus group mentioned in the
text?
A. Mushrooms, molds, and yeasts
B. Molds, yeasts, and algae
C. Mushrooms, algae, and parasites
D. Molds, parasites, and algae

A. Mushrooms, molds, and yeasts

121. How are molds in the Fungi Imperfecti group identified?
A. By their method of sexual reproduction

B. By their method of spore formation
C. By their color and texture
D. By their ability to produce pseudohyphae

B. By their method of spore formation

122. Which fungal group includes the common yeast used in bread baking and beer
production?
A. Zygomycetes
B. Basidiomycetes
C. Ascomycetes
D. Deuteromycetes

C. Ascomycetes

123. What is the primary difference between fungal and plant cell walls?
A. Fungal cell walls are composed of cellulose, while plant cell walls are composed of
chitin.
B. Fungal cell walls are composed of chitin, while plant cell walls are composed of
cellulose.
C. Fungal cell walls lack polysaccharides, while plant cell walls contain polysaccharides.
D. Fungal cell walls have tissue differentiation, while plant cell walls do not.

B. Fungal cell walls are composed of chitin, while plant cell walls are composed of cellulose

124. Which type of fungal spore is formed within a sac called a sporangium?
A. Conidia
B. Chlamydospores
C. Sporangiospores
D. Ascospores

C. Sporangiospores

125. What role do vegetative hyphae play in molds?
A. They produce asexual spores.
B. They anchor the fungus and absorb nutrients.
C. They form visible multicellular colonies.
D. They produce sexual spores.

B. They anchor the fungus and absorb nutrients

126. What is the primary function of hyphae in mycelial fungi?
A. To produce spores
B. To absorb food after decomposing it with enzymes
C. To form cross-walls between cells
D. To produce mushrooms

B. To absorb food after decomposing it with enzymes

127. Which phylum of fungi is responsible for producing most mushrooms?
A. Ascomycota
B. Zygomycota
C. Basidiomycota
D. Chytridiomycota

C. Basidiomycota

What is a notable feature of fungi compared to most bacteria?
A. Fungi do not reproduce through spores.
B. Fungi have cell walls composed of cellulose.
C. Fungi can reproduce both asexually and sexually.
D. Fungi are prokaryotic organisms

C. Fungi can reproduce both asexually and sexually

Why is the Zygomycota group no longer considered an official phylum by fungal
taxonomists?
A. They do not reproduce asexually.
B. They are not an evolutionarily unified group.
C. They do not have coenocytic hyphae.
D. They are not found in everyday human environments.

B. They are not an evolutionarily unified grou

130. What type of symbiotic relationship do lichens represent?
A. Parasitic
B. Commensal
C. Mutualistic
D. Competitive

C. Mutualistic

131. What is a key feature of ectomycorrhizal fungi?
A. They grow inside plant roots.
B. They are found on the roots of conifers and other woody plants.
C. They do not absorb nutrients from the soil.
D. They do not form symbiotic relationships with plants.

B. They are found on the roots of conifers and other woody plants

132. What is a key difference between yeast fungi and mycelial fungi?
A. Yeast fungi are multicellular, while mycelial fungi are unicellular.
B. Yeast fungi have cell walls with a large amount of chitin, while mycelial fungi have
cell walls with a small amount of chitin.
C. Yeast fungi are unicellular, while mycelial fungi are multicellular.
D. Yeast fungi do not contain membrane-bound organelles, while mycelial fungi do.

C. Yeast fungi are unicellular, while mycelial fungi are multicellular

133. Which mechanism is the most common for asexual reproduction in yeasts?
A. Binary fission
B. Spore formation
C. Budding
D. Sexual reproduction

C. Budding

134. What role does S. cerevisiae play in human activities?
A. It causes serious human illnesses.
B. It is used in baking and alcoholic beverage production.
C. It is found on the surfaces of leaves and fruits.
D. It forms part of the normal gut microbiota in humans

B. It is used in baking and alcoholic beverage production

What is the dormant, nonmotile stage in the life cycle of Protozoa called?
A. Trophozoite
B. Sporozoa
C. Cyst
D. Flagellate

C. Cyst

136. Which group of organisms includes mosquitoes, ticks, lice, bed bugs, and fleas?
A. Protozoa
B. Helminthes
C. Arthropods
D. Algae

C. Arthropods

137. What is the primary characteristic of algae that differentiates them from
Protozoa?
A. Algae are non-photosynthetic.
B. Algae contain cellulose and pectin in their cell walls.
C. Algae have a trophozoite stage.
D. Algae are all one-celled organisms.

B. Algae contain cellulose and pectin in their cell walls

138. What is the primary function of the pellicule in protozoa?
A. To aid in motility
B. To protect the cell and assist in food ingestion
C. To facilitate binary fission
D. To produce cysts

B. To protect the cell and assist in food ingestion

139. How are medically important Helminthes classified?
A. By their means of motility
B. By their reproductive system
C. By their phyla: Platyhelminthes and Nematoda
D. By their ability to produce cysts

C. By their phyla: Platyhelminthes and Nematoda

140. What is a characteristic feature of flatworms in the phylum Platyhelminthes?
A. They have a highly developed nervous system.
B. They absorb food directly across a nonliving covering called a cuticle.
C. They are dioecious and display sexual dimorphism.
D. They have a simple life cycle involving a single host.

B. They absorb food directly across a nonliving covering called a cuticle

141. How do members of the Mastigophora move?
A. By using pseudopodia
B. By using cilia
C. By using flagella
D. By gliding

C. By using flagella

142. What is a characteristic feature of organisms classified as Ciliophora?
A. They move using pseudopodia.
B. They have a complex life cycle and are all parasites.
C. They use cilia for movement and feeding.
D. They lack a cell wall

C. They use cilia for movement and feeding

Which organism is the agent of toxoplasmosis?
A. Trichomonas vaginalis
B. Amoeba
C. Toxoplasma gondii
D. Plasmodium falciparum

C. Toxoplasma gondii

144. What is the primary characteristic of the Apicomplexa (Sporozoa)?
A. They move using flagella.
B. They have a complex life cycle and are all parasites.
C. They use cilia for movement.
D. They are free-living organisms.

B. They have a complex life cycle and are all parasites

145. Which organism is observed in a blood smear from a patient with malaria?
A. Trichomonas vaginalis
B. Amoeba
C. Toxoplasma gondii
D. Plasmodium falciparum

D. Plasmodium falciparum

146. What is the shape of the nucleus in Stentor?
A. Oval and brightly stained
B. Crescent moon-shaped
C. Resembling a string of beads
D. Ring-shaped

C. Resembling a string of beads

147. What type of motility do members of Sarcodina (amoeba and related organisms)
use?
A. Flagella
B. Cilia
C. Pseudopodia
D. Gliding

C. Pseudopodia

148. Which organism is associated with the sexually transmitted disease
trichomoniasis?
A. Trichomonas vaginalis
B. Amoeba
C. Toxoplasma gondii
D. Plasmodium falciparum

A. Trichomonas vaginalis

149. What is the function of the contractile vacuoles in Paramecium?
A. Digestion of food
B. Regulation of osmotic balance
C. Movement through water
D. Reproduction

B. Regulation of osmotic balance

Who discovered the ABO blood group system?
A. Alexander Fleming
B. Karl Landsteiner
C. Louis Pasteur
D. Robert Koch

B. Karl Landsteiner

151. What antigens are present on the red blood cells of a person with type AB blood?
A. A antigens only
B. B antigens only
C. Both A and B antigens
D. Neither A nor B antigens

C. Both A and B antigens

152. Which blood type has antibodies against both A and B antigens in their plasma?
A. Type A
B. Type B
C. Type AB
D. Type O

D. Type O

153. What happens during a Type II cytotoxic reaction in an incompatible blood
transfusion?
A. The recipient’s antibodies react with the donor’s RBC antigens.
B. The recipient’s RBCs are lysed by the donor’s antibodies.
C. The recipient’s antibodies attack the donor’s plasma.
D. The donor’s RBCs attack the recipient’s immune cells.

A. The recipient’s antibodies react with the donor’s RBC antigens

154. What is the Rh factor?
A. A type of antibody found in blood plasma
B. An antigen found on RBCs
C. A type of carbohydrate on RBCs
D. A type of immune cell

B. An antigen found on RBCs

155. What can happen if an Rh− mother becomes sensitized to Rh+ blood and
conceives a second Rh+ child?
A. The child will be born without complications.
B. The mother’s antibodies may attack the child’s RBCs.
C. The mother will develop antibodies against A and B antigens.
D. The child will develop antibodies against Rh factor.

B. The mother’s antibodies may attack the child’s RBCs

156. What is hemolytic disease of the newborn (HDNB)?
A. A condition where the mother’s antibodies attack the child’s RBCs.
B. A condition where the child’s antibodies attack the mother’s RBCs.
C. A condition where the child’s RBCs attack the mother’s immune cells.
D. A condition where the mother’s RBCs attack the child’s immune cells.

A. A condition where the mother’s antibodies attack the child’s RBCs

Why are individuals with type O blood called “universal donors”?
A. They have both A and B antigens.
B. They have neither A nor B antigens.
C. They have antibodies against all blood types.
D. They can receive blood from any donor.

B. They have neither A nor B antigens

158. Why are individuals with type AB blood called “universal recipients”?
A. They have antibodies against all blood types.
B. They have neither A nor B antigens.
C. They can receive blood from any donor without adverse reactions.
D. They can donate blood to any recipient without adverse reactions.

C. They can receive blood from any donor without adverse reactions

159. What triggers the production of antibodies against Rh factor in an Rh− person?
A. Exposure to Rh− blood
B. Exposure to Rh+ blood
C. Exposure to A and B antigens
D. Exposure to type O blood

B. Exposure to Rh+ blood