Microbiology Exam
Below are sample questions from this exam to help you understand the content and format.
Q1: What drug is most often used in fighting protozoan infections of the reproductive system?
Answer Choices:
⮞ Metronidazole is the drug of choice for trichomoniasis, a protozoan infection of the reproductive tract.
⮞ It works by disrupting DNA synthesis in anaerobic organisms and protozoa.
⮞ Tetracycline and ciprofloxacin are antibiotics used against bacteria, not protozoa.
⮞ Ampicillin is a beta-lactam antibiotic effective for bacterial infections but not protozoal infections.
Q2: Which bacteria causes acne?
Answer Choices:
⮞ Propionibacterium acnes (recently renamed Cutibacterium acnes) is the primary bacterial species implicated in acne vulgaris.
⮞ It contributes to acne by blocking sebaceous glands and causing inflammation.
⮞ Staphylococcus epidermidis and aureus can cause skin infections but are not the main cause of acne.
⮞ Streptococcus pyogenes is associated with pharyngitis and skin infections like impetigo, not acne.
Q3: Which infection is caused by Streptococcus agalactiae and is a leading cause of life-threatening illness and death in newborns?
Answer Choices:
⮞ Streptococcus agalactiae is also known as Group B Streptococcus (GBS).
⮞ GBS can cause sepsis, pneumonia, and meningitis in newborns, often transmitted during childbirth.
⮞ Group A Streptococcus is associated with strep throat and rheumatic fever.
⮞ Group C Streptococcus is much less common and not typically associated with neonatal infection.
⮞ Cervical inflammation is not specific to Streptococcus agalactiae.
Q4: Where do the human pinworms, enterobius vermicularis, generally live in the human body?
Answer Choices:
✍️ Enterobius vermicularis (pinworm) typically inhabits the rectum and lower intestine.
✍️ At night, female worms migrate to the anal opening to lay eggs, causing perianal itching.
✍️ They do not live in the stomach, duodenum, or transverse colon.
✍️ This rectal location explains why infection is diagnosed by the tape test around the anus.
Q5: What are the three most commonly occurring sexually transmitted infections (STIs) on college campuses? Select all that apply.
Answer Choices:
✔ Human papillomavirus (HPV)
⮞ HPV is the most common STI on college campuses, affecting a large proportion of sexually active young adults.
⮞ It is often asymptomatic, but certain strains can cause genital warts and cervical cancer.
⮞ Vaccination helps prevent high-risk HPV types but many students may be unvaccinated.
⮞ Its high prevalence makes HPV one of the top STIs among college students.
✔ Gonorrhea
⮞ Gonorrhea is caused by Neisseria gonorrhoeae and is another common STI among young adults.
⮞ It frequently coexists with chlamydia infections, leading to dual treatment.
⮞ Many cases are asymptomatic, particularly in women, increasing risk of pelvic inflammatory disease (PID) if untreated.
⮞ Its prevalence on campuses is high due to unprotected sexual activity and asymptomatic spread.
✔ Chlamydia
⮞ Chlamydia trachomatis infection is one of the leading bacterial STIs in college-age populations.
⮞ It is often called a “silent infection” because most carriers are asymptomatic.
⮞ Without treatment, chlamydia can cause infertility, PID, and chronic pelvic pain.
⮞ Routine screening is recommended in sexually active young women due to its high occurrence rate.
