The annotation D refers to which DNA component?
- A. Plasmid DNA
- B. Vector DNA
- C. Insert DNA
- D. Recombinant DNA
Correct Answer: D
Rationale: The correct answer is D: Recombinant DNA. Recombinant DNA refers to the DNA molecule formed by combining DNA from different sources. In genetic engineering, this is created by inserting a foreign DNA fragment into a vector DNA, resulting in a new DNA molecule. Plasmid DNA (A) is a small, circular DNA found in bacteria. Vector DNA (B) is a carrier molecule used to transport foreign DNA into a host cell. Insert DNA (C) is the DNA fragment that is inserted into a vector. Therefore, choice D is the correct answer as it specifically refers to the combined DNA molecule formed in genetic engineering.
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Carpal tunnel syndrome (CTS) is caused when the carpal tunnel compresses which location?
- A. Radial artery
- B. Brachial artery
- C. Median nerve
- D. Ulnar nerve
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.
To prevent the debilitating cycle of fatigue-depression-fatigue in patients receiving radiation therapy, what should the nurse encourage the patient to do?
- A. Implement a walking program
- B. Ignore the fatigue as much as possible
- C. Do the most stressful activities when fatigue is tolerable
- D. Schedule rest periods throughout the day whether fatigue is present or not
Correct Answer: D
Rationale: Scheduled rest periods help break the cycle of fatigue and depression.
Many clients with chronic fatigue syndrome (CFS) report severe,ongoing fatigue without any explanation that has lasted for at least — months.
- A. 12
- B. 6
- C. 3
- D. 2
Correct Answer: B
Rationale: Chronic fatigue syndrome is characterized by severe unexplained fatigue lasting for at least six months.
After engagement of its pattern recognition receptors what happens to a dendritic cell to enable its role in naïve T cell activation?
- A. Expression of MHC class I molecules begins
- B. Increased uptake of antigens
- C. Expression of the B7 molecule
- D. PAMP-induced proliferation
Correct Answer: C
Rationale: After engagement of pattern recognition receptors, dendritic cells upregulate expression of the B7 molecule, which is essential for co-stimulation of naïve T cells. This step is crucial for activating T cells. MHC class I molecules present antigens to CD8+ T cells, not CD4+ T cells, so choice A is incorrect. Dendritic cells already have high antigen uptake ability, so choice B is not directly related to activation. PAMP-induced proliferation is not a typical response of dendritic cells after pattern recognition receptor engagement, making choice D incorrect.
A critical role of secondary lymphoid tissues is to:
- A. Provide a place for B and T lymphocytes to mature and begin expression of antigen receptors
- B. Allow co-localization of the components required to activate naïve lymphocytes
- C. Minimize contact of naïve lymphocytes with self antigens
- D. All of the above
Correct Answer: B
Rationale: Step 1: Secondary lymphoid tissues bring together antigen-presenting cells and lymphocytes, facilitating the activation of naïve lymphocytes.
Step 2: Co-localization of these components is essential for efficient immune response initiation.
Step 3: Maturation and expression of antigen receptors primarily occur in primary lymphoid tissues, not secondary.
Summary:
A: Incorrect. Maturation of lymphocytes occurs mainly in primary lymphoid tissues.
C: Incorrect. Contact with self-antigens is necessary for self-tolerance and occurs in primary lymphoid tissues.
D: Incorrect. Only choice B accurately describes the critical role of secondary lymphoid tissues.