The lysozyme hydrolyzes:

Correct Answer: A

Rationale: The correct answer is A: The lysozyme hydrolyzes the glycoside bonds between the N-acetylmuramic acid and the N-acetylglucosamine in the peptidoglycan of the cell wall. This is because lysozyme is an enzyme that specifically targets the peptidoglycan layer of bacterial cell walls, breaking down the structure by cleaving the glycosidic bonds between these two specific sugar molecules. This action weakens the cell wall, leading to bacterial cell lysis. The other choices are incorrect because lysozyme does not target phosphate bonds in phospholipids (B), disulfide bonds in immunoglobulins (C), or hydrogen bonds in bacterial capsules (D).

Correct Answer: D

Rationale: The correct answer is D: Chlamydia trachomatis. Lymphogranuloma venereum (LGV) is caused by Chlamydia trachomatis serovars L1, L2, and L3. These serovars infect the lymphatic system leading to swelling and inflammation. Choice A, Chlamydia pneumoniae, is associated with respiratory infections, not LGV. Choice B, Chlamydia psittaci, causes psittacosis in birds and humans. Choice C, Mycoplasma genitalium, is a separate STI but is not the causative agent for LGV. The key to the correct answer is understanding the specific pathogen responsible for LGV based on its clinical presentation and mode of transmission.

Correct Answer: D

Rationale: The correct answer is D because all of these symptoms are early signs of rabies. A short period of depression, nausea, and restlessness are common initial symptoms of rabies infection. These symptoms may be followed by more severe manifestations, such as aggression, confusion, and difficulty swallowing. Therefore, option D is the correct choice as it encompasses all the early symptoms of rabies. Options A, B, and C are incorrect as they focus on individual symptoms, whereas rabies typically presents with a combination of these early signs.

Correct Answer: B

Rationale: The correct answer is B: Sporadic disease. When an infection occurs in several persons without any epidemiological link, it is considered sporadic. This term is used to describe isolated cases that do not form a specific pattern or cluster. It indicates random occurrences and lack of connection between the affected individuals. A: Epidemic refers to a sudden increase in the number of cases of a disease within a specific population or region, usually linked by a common source or exposure. C: Endemic signifies the constant presence of a disease within a specific population or region, with cases occurring at a relatively stable rate. D: Pandemic indicates a global outbreak of a disease affecting a large number of people across multiple countries or continents.

Correct Answer: B

Rationale: The correct answer is B because the AST reaction, or anti-streptolysin titer, is used in the diagnostic of post-streptococcal sequelae, such as rheumatic fever and glomerulonephritis. This test measures the level of antibodies produced by the body in response to Streptolysin O, a toxin produced by Group A Streptococcus bacteria. It helps in identifying if a patient has had a recent Streptococcus infection that could lead to these complications. A: Incorrect. The AST reaction does not require urine samples, but rather blood samples. C: Incorrect. The AST reaction specifically targets antibodies produced in response to Group A Streptococcus. D: Incorrect. The AST reaction does not directly identify isolated streptococci but rather measures the body's immune response to Streptolysin O.