What drug should be administered for individual prevention of malaria?

Correct Answer: A

Rationale: The correct answer is A: Chingamin. Chingamin is a type of antimalarial drug that is commonly used for individual prevention of malaria. It works by targeting the malaria parasite in the body, preventing its growth and spread. Rifampicin (B), Ampicillin (C), and Gentamicin (D) are not effective for preventing malaria as they are antibiotics that target bacterial infections, not parasitic infections like malaria. Therefore, Chingamin is the most appropriate choice for individual prevention of malaria due to its specific antimalarial properties.

Correct Answer: D

Rationale: The correct answer is D: Neuraminidase inhibitors. Neuraminidase is an enzyme crucial for the release of new viral particles from infected cells during influenza infection. By inhibiting neuraminidase, the spread of the virus is limited. Protease inhibitors (choice A) are used to treat HIV, not influenza. Beta-lactamase inhibitors (choice B) are used in combination with beta-lactam antibiotics to increase their effectiveness against bacteria, not viruses. Reverse transcriptase inhibitors (choice C) are used to treat HIV by blocking the enzyme responsible for replicating the virus's genetic material, but they are not effective against influenza.

Correct Answer: A

Rationale: The correct answer is A: protein envelope around the nucleic acid. Viral capsid is the protein coat that surrounds and protects the viral nucleic acid (DNA or RNA). This structure helps in protecting the genetic material from degradation and facilitates the attachment of the virus to host cells. Option B is incorrect as it suggests the nucleic acid is coated with protein, which is not the case. Option C is incorrect as not all viruses have an outer membrane. Option D is incorrect as viruses typically do not have a lipoprotein membrane.

Correct Answer: B

Rationale: The correct answer is B: psittacosis. Psittacosis is an infection caused by Chlamydia psittaci that primarily affects the lower respiratory tract, leading to pneumonia-like symptoms. Mycoplasma pneumoniae causes atypical pneumonia, not pharyngitis (Choice A). Chronic atrophic rhinitis (Choice C) and rhinoscleroma (Choice D) both affect the upper respiratory tract, not the lower respiratory tract. Psittacosis specifically targets the lower respiratory tract, making it the most appropriate answer.

Correct Answer: D

Rationale: The correct answer is D: Mycoplasma. Mycoplasma is the only bacteria among the choices that have sterols in their cytoplasmic membrane. This feature helps stabilize their membrane structure due to the lack of a cell wall. Legionella (A), Bacillus (B), and Rickettsia (C) do not contain sterols in their cytoplasmic membrane. Legionella has a unique lipid composition, Bacillus has peptidoglycan in its cell wall, and Rickettsia is an intracellular parasite lacking sterols in its membrane.

Correct Answer: D

Rationale: The correct answer is D because Mycobacterium tuberculosis is a straight or slightly curved rod with occasional polymorphism. This bacterium does not conform to the characteristics of gram-negative coccus (A), gram-positive coccus (B), or gram-negative rod (C). Mycobacterium tuberculosis is characterized by its unique cell wall composition, which includes high lipid content and mycolic acids, contributing to its acid-fast staining property. The other choices are incorrect because they do not accurately describe the morphology of Mycobacterium tuberculosis.

Correct Answer: D

Rationale: The correct answer is D (All of the above). All three bacteria (Escherichia coli, Salmonella enterica, Pseudomonas aeruginosa) produce endotoxins that can lead to septic shock. Endotoxins are part of the outer membrane of Gram-negative bacteria and can trigger a strong immune response, leading to septic shock when released in large amounts. Escherichia coli and Salmonella enterica are common causes of bacterial septic shock, while Pseudomonas aeruginosa is known for its ability to produce endotoxins that contribute to severe infections and septic shock. Therefore, all three choices are correct in this context.

Correct Answer: B

Rationale: The correct answer is B: Bacillus subtilis. Bacillus subtilis is known for its ability to resist heat and radiation due to its formation of endospores, which are highly resistant structures that protect the bacterium from harsh environmental conditions. This resilience allows Bacillus subtilis to survive in extreme environments where other bacteria cannot. Explanation of other choices: A: Escherichia coli is not known for its exceptional resistance to heat and radiation. C: Pseudomonas aeruginosa is not particularly resistant to heat and radiation compared to Bacillus subtilis. D: Clostridium perfringens is not as well-known for its heat and radiation resistance as Bacillus subtilis.

Correct Answer: A

Rationale: The correct sequence of stages in the multiplication of animal viruses is as follows: 1. Adsorption: Virus attaches to host cell. 2. Penetration: Virus enters host cell. 3. Uncoating: Viral genetic material is released. 4. Replication: Viral genetic material replicates. 5. Assembly: New viral particles are assembled. 6. Release: New viral particles are released from the host cell. Choice A is correct as it follows the correct chronological order of virus multiplication stages. Choice B is incorrect as it has the wrong order of penetration and adsorption. Choice C is incorrect as it has the wrong order of adsorption, uncoating, and penetration. Choice D is incorrect as it has the wrong order of penetration and uncoating.