651. MacConkey agar is an example of?
A. General purpose medium
B. Enrichment medium
C. Differential medium ✅
D. Enriched medium
A. General purpose medium
B. Enrichment medium
C. Differential medium ✅
D. Enriched medium
652. Which of the following is the most commonly affected non-pulmonary site by Mycoplasma?
A. Meningitis
B. Prosthetic heart valve
C. Septic arthritis ✅
D. Urethritis
A. Meningitis
B. Prosthetic heart valve
C. Septic arthritis ✅
D. Urethritis
653. Which of the following is the current preferred antimicrobial treatment of cutaneous anthrax?
A. Aminoglycosides
B. Ciprofloxacin ✅
C. Penicillin
D. Tetracycline
A. Aminoglycosides
B. Ciprofloxacin ✅
C. Penicillin
D. Tetracycline
654. Bacillus anthracis is unique to other bacteria. It is the only bacteria to possess which of the following?
A. An endotoxin
B. A polypeptide capsule ✅
C. A polysaccharide capsule
D. Teichoic acid in its outer cell wall
A. An endotoxin
B. A polypeptide capsule ✅
C. A polysaccharide capsule
D. Teichoic acid in its outer cell wall
655. Which of the following diseases could also be transmitted by ticks?
A. Q fever
B. Leptospirosis
C. Ehrlichiosis ✅
D. Yellow fever
A. Q fever
B. Leptospirosis
C. Ehrlichiosis ✅
D. Yellow fever
656. Which of the following are the special laboratory conditions needed to recover C. jejuni?
A. 98.6 oF (37 oC) aerobic blood agar plates
B. 98.6 oF (37 oC) anaerobic blood agar plates
C. 107.6 oF (42 oC) microaerophilic Skirrow medium ✅
D. 107.6 oF (42 oC) anaerobic Skirrow medium
A. 98.6 oF (37 oC) aerobic blood agar plates
B. 98.6 oF (37 oC) anaerobic blood agar plates
C. 107.6 oF (42 oC) microaerophilic Skirrow medium ✅
D. 107.6 oF (42 oC) anaerobic Skirrow medium
657. Testing of blood culture revealed Gram-positive cocci, vancomycin-resistant, PYR-positive and the presence of Lancefield group D antigen. Which of the following is the most likely isolate identification?
A. Enterococcus faecalis ✅
B. Staphylococcus aureus
C. Streptococcus pneumoniae
D. Streptococcus agalactiae
A. Enterococcus faecalis ✅
B. Staphylococcus aureus
C. Streptococcus pneumoniae
D. Streptococcus agalactiae
658. Verotoxin producing E. coli O157:H7 serotype belongs to which group?
A. Enteroaggregative E. coli (EAEC)
B. Enterohemorrhagic E. coli (EHEC) ✅
C. Enteroinvasive E. coli (EIEC)
D. Enterotoxigenic E. coli (ETEC)
A. Enteroaggregative E. coli (EAEC)
B. Enterohemorrhagic E. coli (EHEC) ✅
C. Enteroinvasive E. coli (EIEC)
D. Enterotoxigenic E. coli (ETEC)
659. Which of the following is a key typical characteristic of H. pylori as compared to Campylobacter species?
A. Coagulase production
B. Catalase production
C. Urease production ✅
D. Curved shape
A. Coagulase production
B. Catalase production
C. Urease production ✅
D. Curved shape
660. A 4-year-old has fever and diarrhea. Blood culture grows a Gram-negative rod. This is most likely to be which of the following?
A. Group B Streptococcus
B. Listeria species
C. Salmonella species ✅
D. Neisseria species
A. Group B Streptococcus
B. Listeria species
C. Salmonella species ✅
D. Neisseria species
661. The O antigen used to help characterize members of Enterobacteriaceae are found on:
A. Capsules
B. Endotoxins ✅
C. Exotoxins
D. Flagella
A. Capsules
B. Endotoxins ✅
C. Exotoxins
D. Flagella
662. The most frequent source of L. monocytogenes infection is through which of the following?
A. Human feces
B. Soil
C. Raw milk ✅
D. Ticks
A. Human feces
B. Soil
C. Raw milk ✅
D. Ticks
663. The ability of the Neisseria meningitidis to colonize the respiratory mucosa is associated with its ability to synthesize:
A. Coagulase
B. Collagenase
C. Lipases
D. Pilli ✅
A. Coagulase
B. Collagenase
C. Lipases
D. Pilli ✅
664. UTI as a result of Proteus mirabilis facilitates the formation of kidney stones because the organism does which of the following?
A. Destroys blood vessels in the kidney
B. Exhibits ‘swarming’ motility
C. Ferments many sugars
D. Produces a potent urease ✅
A. Destroys blood vessels in the kidney
B. Exhibits ‘swarming’ motility
C. Ferments many sugars
D. Produces a potent urease ✅
665. A woman is noted to have pyelonephritis with shaking chills and fever. Blood cultures are obtained and the Gram-negative is read preliminary as consistent with Proteus species. Which of the following bacteria also may be the etiology?
A. Escherichia coli ✅
B. Group B Streptococcus
C. Staphylococcus aureus
D. Streptococcus pyogenes
A. Escherichia coli ✅
B. Group B Streptococcus
C. Staphylococcus aureus
D. Streptococcus pyogenes
666. A man is diagnosed with meningitis. CSF grows out Gram-positive diplococci. This is most likely to be:
A. Neisseria meningitidis
B. Staphylococcus aureus
C. Salmonella typhi
D. Streptococcus pneumoniae ✅
A. Neisseria meningitidis
B. Staphylococcus aureus
C. Salmonella typhi
D. Streptococcus pneumoniae ✅
667. Which of the following viral families is known to be causally associated with tumor formation?
A. Flavivirus
B. Papovavirus ✅
C. Retrovirus
D. Picornavirus
A. Flavivirus
B. Papovavirus ✅
C. Retrovirus
D. Picornavirus
668. The process of transcription refers to:
A. DNA to RNA ✅
B. RNA to protein
C. Protein to DNA
D. DNA to DNA
A. DNA to RNA ✅
B. RNA to protein
C. Protein to DNA
D. DNA to DNA
669. A common method for sterilizing liquids in the laboratory is:
A. Autoclaving ✅
B. Freezing
C. Boiling
D. Filtration
A. Autoclaving ✅
B. Freezing
C. Boiling
D. Filtration
670. Which of the following is NOT a characteristic of bacteria?
A. They are eukaryotic ✅
B. They can reproduce independently
C. They have a cell wall
D. They lack membrane-bound organelles
A. They are eukaryotic ✅
B. They can reproduce independently
C. They have a cell wall
D. They lack membrane-bound organelles
671. Which of the following techniques is used to detect the presence of specific proteins in a sample?
A. PCR
B. ELISA ✅
C. Southern blotting
D. Gel electrophoresis
A. PCR
B. ELISA ✅
C. Southern blotting
D. Gel electrophoresis
672. Bacterial DNA is found in the:
A. Nucleus
B. Cytoplasm ✅
C. Ribosome
D. Cell membrane
A. Nucleus
B. Cytoplasm ✅
C. Ribosome
D. Cell membrane
673. The process by which bacteria take up naked DNA from the environment is known as:
A. Conjugation
B. Transduction
C. Transformation ✅
D. Transfection
A. Conjugation
B. Transduction
C. Transformation ✅
D. Transfection
674. Which of the following statements regarding antibiotics is correct?
A. They are effective against viruses
B. They are produced by bacteria or fungi ✅
C. They can be used to treat all infections
D. They have no side effects
A. They are effective against viruses
B. They are produced by bacteria or fungi ✅
C. They can be used to treat all infections
D. They have no side effects
675. Which of the following is a type of white blood cell involved in the immune response?
A. Red blood cell
B. Platelet
C. Lymphocyte ✅
D. Neutrophil
A. Red blood cell
B. Platelet
C. Lymphocyte ✅
D. Neutrophil
676. The most common type of vaccine is:
A. Live attenuated
B. Inactivated ✅
C. Subunit
D. DNA
A. Live attenuated
B. Inactivated ✅
C. Subunit
D. DNA
677. The main role of the microbiome in human health is to:
A. Cause disease
B. Aid digestion and provide protection ✅
C. Produce toxins
D. Induce allergies
A. Cause disease
B. Aid digestion and provide protection ✅
C. Produce toxins
D. Induce allergies
678. The primary role of antibodies in the immune response is to:
A. Kill pathogens
B. Neutralize toxins ✅
C. Produce cytokines
D. Activate T cells
A. Kill pathogens
B. Neutralize toxins ✅
C. Produce cytokines
D. Activate T cells
679. The primary site of bacterial infection in humans is:
A. Skin
B. Mucous membranes ✅
C. Blood
D. Bone
A. Skin
B. Mucous membranes ✅
C. Blood
D. Bone
680. The presence of a capsule around a bacterium enhances its:
A. Motility
B. Virulence ✅
C. Growth rate
D. Oxygen requirements
A. Motility
B. Virulence ✅
C. Growth rate
D. Oxygen requirements
681. The most common cause of viral gastroenteritis in children is:
A. Rotavirus ✅
B. Norovirus
C. Adenovirus
D. Astrovirus
A. Rotavirus ✅
B. Norovirus
C. Adenovirus
D. Astrovirus
682. Which of the following viruses is known to cause cervical cancer?
A. Human Papillomavirus (HPV) ✅
B. Hepatitis B Virus
C. Epstein-Barr Virus
D. Human Immunodeficiency Virus (HIV)
A. Human Papillomavirus (HPV) ✅
B. Hepatitis B Virus
C. Epstein-Barr Virus
D. Human Immunodeficiency Virus (HIV)
683. The primary route of transmission for the common cold is:
A. Fecal-oral
B. Airborne ✅
C. Blood
D. Direct contact
A. Fecal-oral
B. Airborne ✅
C. Blood
D. Direct contact
684. The structure that protects bacteria from phagocytosis is called:
A. Cell wall
B. Capsule ✅
C. Cytoplasmic membrane
D. Pili
A. Cell wall
B. Capsule ✅
C. Cytoplasmic membrane
D. Pili
685. A common method used to sterilize culture media is:
A. Autoclaving ✅
B. Dry heat
C. Ethylene oxide
D. Filtration
A. Autoclaving ✅
B. Dry heat
C. Ethylene oxide
D. Filtration
686. The method used to separate and analyze proteins is:
A. DNA sequencing
B. Gel electrophoresis ✅
C. PCR
D. Cloning
A. DNA sequencing
B. Gel electrophoresis ✅
C. PCR
D. Cloning
687. The total number of colonies on a plate is referred to as:
A. CFU ✅
B. MPN
C. Titer
D. Density
A. CFU ✅
B. MPN
C. Titer
D. Density
688. A major feature of the innate immune system is:
A. Specificity
B. Memory
C. Immediate response ✅
D. Clonal selection
A. Specificity
B. Memory
C. Immediate response ✅
D. Clonal selection
689. The type of immunity that develops after exposure to a pathogen is:
A. Innate immunity
B. Passive immunity
C. Active immunity ✅
D. Herd immunity
A. Innate immunity
B. Passive immunity
C. Active immunity ✅
D. Herd immunity
690. The structure that helps bacteria attach to surfaces is:
A. Capsule
B. Flagella
C. Fimbriae ✅
D. Cell wall
A. Capsule
B. Flagella
C. Fimbriae ✅
D. Cell wall
691. A disease that can be transmitted from animals to humans is:
A. Zoonosis ✅
B. Endemic disease
C. Epidemic disease
D. Pandemic disease
A. Zoonosis ✅
B. Endemic disease
C. Epidemic disease
D. Pandemic disease
692. A common method of sterilization used in laboratories is:
A. Boiling
B. Autoclaving ✅
C. Disinfection
D. Antisepsis
A. Boiling
B. Autoclaving ✅
C. Disinfection
D. Antisepsis
693. The characteristic shape of bacteria can be determined by:
A. Cell wall composition
B. Genetic material
C. Nutritional requirements
D. All of the above ✅
A. Cell wall composition
B. Genetic material
C. Nutritional requirements
D. All of the above ✅
694. Which of the following is NOT a characteristic of viruses?
A. They can replicate on their own ✅
B. They are smaller than bacteria
C. They contain either DNA or RNA
D. They require a host cell to reproduce
A. They can replicate on their own ✅
B. They are smaller than bacteria
C. They contain either DNA or RNA
D. They require a host cell to reproduce
695. The process of sterilizing heat-sensitive items is called:
A. Autoclaving
B. Ethylene oxide ✅
C. Boiling
D. Dry heat
A. Autoclaving
B. Ethylene oxide ✅
C. Boiling
D. Dry heat
696. The process of DNA replication is:
A. Transcription
B. Translation
C. Duplication ✅
D. Transformation
A. Transcription
B. Translation
C. Duplication ✅
D. Transformation
697. The most common method of diagnosing bacterial infections is:
A. Blood culture ✅
B. PCR
C. ELISA
D. Western blot
A. Blood culture ✅
B. PCR
C. ELISA
D. Western blot
698. The primary component of the bacterial cell wall is:
A. Peptidoglycan ✅
B. Lipopolysaccharide
C. Proteins
D. Nucleic acids
A. Peptidoglycan ✅
B. Lipopolysaccharide
C. Proteins
D. Nucleic acids
699. The most common bacterial cause of pneumonia is:
A. Streptococcus pneumoniae ✅
B. Staphylococcus aureus
C. Escherichia coli
D. Klebsiella pneumoniae
A. Streptococcus pneumoniae ✅
B. Staphylococcus aureus
C. Escherichia coli
D. Klebsiella pneumoniae
700. The main component of bacterial capsules is:
A. Lipids
B. Polysaccharides ✅
C. Proteins
D. Nucleic acids
A. Lipids
B. Polysaccharides ✅
C. Proteins
D. Nucleic acids