Carpal tunnel syndrome (CTS) is caused when the carpal tunnel compresses which location?

Correct Answer: C

Rationale: The correct answer is C: Median nerve. Carpal tunnel syndrome occurs when the median nerve is compressed within the carpal tunnel in the wrist. This compression leads to symptoms like numbness, tingling, and weakness in the hand and fingers. The other choices are incorrect because the radial artery (A) and the brachial artery (B) are blood vessels, not nerves. The ulnar nerve (D) runs along a different path in the arm and is not involved in carpal tunnel syndrome.

Correct Answer: A

Rationale: The correct answer is A: Blood. Naïve T cells are circulating in the blood, ready to encounter antigens. They can move to secondary lymphoid organs like lymph nodes. Germinal centers (B) are sites of B cell maturation, not where naïve T cells are primarily found. While some naïve T cells enter lymph nodes (C), they are not mostly located in the medullary region. Naïve T cells can also migrate to non-lymphoid tissues (D), but their primary residence is in the blood.

Correct Answer: D

Rationale: The correct answer is D because dendritic cells do not typically move rapidly through the germinal center during an immune response. Dendritic cells usually interact with T cells in the paracortex to present antigens, and they are not known to migrate rapidly through the germinal center. A: This statement is correct as T cells do make stable and prolonged contacts with APCs in the paracortex during immune responses. B: This statement is incorrect as B cells do not move at the same speed and randomly in follicles in the absence of antigens. They respond to signals and cues in the microenvironment. C: This statement is correct as specific B cells can quickly direct themselves towards the source of antigen during an infection. In summary, choice D is incorrect because dendritic cells do not move rapidly through the germinal center during an immune response, while the other choices accurately describe behaviors of immune cells during immune responses.

Correct Answer: C

Rationale: The correct answer is C because it indicates a specific reason for the intense debate within the scientific community regarding ferrets in Flu research. Mutations in H5N1 creating a strain transmissible among ferrets is significant as it highlights a potential threat of cross-species transmission and the need for further study. A is incorrect as it does not provide a specific reason related to ferrets and their role in Flu research. B is incorrect because it focuses on a specific strain (H1N1) rather than mutations in H5N1. D is incorrect as it mentions publications being put on hold but does not address the core issue of mutations and transmissibility among ferrets.

Correct Answer: B

Rationale: Step-by-step rationale for Choice B (IL-1β) being correct: 1. The TIR domain is present in Toll-like receptors (TLRs) and IL-1 receptor. 2. TLRs recognize various microbial products, while IL-1 receptor binds IL-1 cytokines. 3. Both TLRs and IL-1 receptor signal through the TIR domain. 4. IL-1β is a cytokine that binds to IL-1 receptor, which contains a TIR domain. Summary of why the other choices are incorrect: A: Type I Interferons - Type I interferons signal through JAK-STAT pathway, not TIR domain. C: TNF-α - TNF receptor family signals through TNF receptor-associated death domain, not TIR domain. D: IL-8 - IL-8 binds to CXCR1 and CXCR2 receptors, which do not contain a TIR domain. In summary, Choice B