Nokea
Which of the following hepatitis viruses is NOT a RNA virus?
- A. Hepatitis G virus
- B. Hepatitis B virus
- C. Hepatitis A virus
- D. Hepatitis E virus
Correct Answer: B
Rationale: The correct answer is B: Hepatitis B virus. This is because Hepatitis B virus is a DNA virus, not an RNA virus. The other choices, A (Hepatitis G virus), C (Hepatitis A virus), and D (Hepatitis E virus) are all RNA viruses. Hepatitis B virus is unique as it contains partially double-stranded DNA. DNA viruses replicate through a DNA intermediate, unlike RNA viruses which directly use RNA. Therefore, Hepatitis B virus stands out as the only DNA virus among the given options.
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What preventive medications should be injected to a patient with open maxillofacial trauma provided that he has never got prophylactic vaccination before?
- A. Antitetanus immunoglobulin and anatoxin
- B. Anticonvulsive drugs and anatoxin
- C. Antitetanus serum and antibiotics
- D. Diphtheria, tetanus toxoids and pertussis vaccine and antibiotics
Correct Answer: C
Rationale: Step 1: Antitetanus serum is crucial for patients with open maxillofacial trauma to prevent tetanus infection from contaminated wounds.
Step 2: Antibiotics are needed to prevent infection in the wound.
Step 3: Antitetanus serum provides immediate passive immunity while antibiotics help combat potential infections.
Step 4: Antitetanus immunoglobulin is not mentioned in the question and is not typically used for prophylaxis.
Step 5: Anticonvulsive drugs are not preventive medications for maxillofacial trauma.
Step 6: Diphtheria, tetanus, and pertussis vaccines are not specifically indicated for immediate prevention in this scenario.
Which bacteria is known for producing an exotoxin that causes severe diarrhea?
- A. Vibrio cholerae
- B. Clostridium botulinum
- C. Streptococcus pyogenes
- D. Salmonella enterica
Correct Answer: A
Rationale: Rationale: Vibrio cholerae produces the exotoxin responsible for severe diarrhea. It causes cholera by disrupting the normal functioning of the intestines. Clostridium botulinum causes botulism, not diarrhea. Streptococcus pyogenes causes strep throat and skin infections. Salmonella enterica causes food poisoning, not severe diarrhea. Therefore, the correct answer is A.
A puncture sample has been taken from the inguinal lymph nodes of a patient provisionally diagnosed with plague. The sample was inoculated into a hard nutrient medium. What shape will the colonies have, if the diagnosis is confirmed?
- A. Dewdrops
- B. Shagreen leather
- C. Lace handkerchief
- D. Mercury drops
Correct Answer: B
Rationale: The correct answer is B: Shagreen leather. Yersinia pestis, the bacterium causing plague, forms colonies resembling shagreen leather on a hard nutrient medium due to its distinctive morphology. This morphology includes a rough, irregular, and raised appearance, similar to the texture of shagreen leather.
A: Dewdrops - Incorrect. Dewdrops do not accurately describe the colony morphology of Yersinia pestis.
C: Lace handkerchief - Incorrect. Lace handkerchief does not accurately describe the colony morphology of Yersinia pestis.
D: Mercury drops - Incorrect. Mercury drops do not accurately describe the colony morphology of Yersinia pestis.
Secondary immune response produces much more antibodies than a primary immune response but it is slower than the primary one.
- A. TRUE
- B. FALSE
- C. Both answers can be correct depending on the given situation
- D. None of the above
Correct Answer: B
Rationale: The correct answer is B: FALSE. The statement is incorrect because the secondary immune response is actually faster than the primary immune response. This is due to memory cells that are formed during the primary response, allowing for a quicker and more robust reaction upon re-exposure to the same antigen. The secondary response produces more antibodies and is more effective in clearing the pathogen. Choice A is incorrect because the secondary response is faster, not slower. Choice C is incorrect because the statement is objectively false, regardless of the situation. Choice D is incorrect as the correct answer is B.
A Gram-positive, spore-forming bacterium was isolated from a wound infection. The bacteria were anaerobic and produced gas. What is the likely causative agent?
- A. Clostridium perfringens
- B. Bacillus anthracis
- C. Clostridium botulinum
- D. Clostridium tetani
Correct Answer: A
Rationale: The correct answer is A: Clostridium perfringens. This bacterium is Gram-positive, spore-forming, anaerobic, and produces gas. Clostridium perfringens is commonly associated with wound infections due to its ability to produce gas gangrene.
Choice B: Bacillus anthracis is also a Gram-positive, spore-forming bacterium, but it does not typically produce gas in wound infections.
Choice C: Clostridium botulinum is a spore-forming, anaerobic bacterium, but it is associated with foodborne botulism rather than wound infections.
Choice D: Clostridium tetani is a spore-forming, anaerobic bacterium that causes tetanus, but it does not produce gas in wound infections.