Which of the following is correct about lectin receptors?
- A. They recognize microbial carbohydrates
- B. They are expressed on phagocytes
- C. They can be classified as pattern recognition receptors
- D. All of the above is correct
Correct Answer: D
Rationale: The correct answer is D - All of the above. Lectin receptors recognize microbial carbohydrates, are expressed on phagocytes, and can be classified as pattern recognition receptors. Lectins are proteins that bind specifically to certain carbohydrates, allowing them to recognize and interact with pathogens. Phagocytes express lectin receptors to help identify and engulf pathogens. Additionally, lectin receptors are considered pattern recognition receptors because they recognize specific patterns or structures commonly found on pathogens. Therefore, all three statements are true, making option D the correct answer.
You may also like to solve these questions
The nurse is caring for a patient who just returned from surgical decompression of the carpal tunnel. Which finding requires the nurse's immediate action?
- A. The patient's fingers swollen and warm.
- B. The patient complains of generalized pain 5/10.
- C. The capillary refill time is 8 seconds.
- D. The patient's fingers are pink and cool bilaterally.
Correct Answer: C
Rationale: The correct answer is C because a capillary refill time of 8 seconds indicates poor perfusion, which could be a sign of compromised blood flow to the fingers post-surgical decompression. This finding requires immediate action to prevent complications such as ischemia or impaired wound healing.
A: Swollen and warm fingers are expected after surgery due to inflammation.
B: Generalized pain can be managed with appropriate pain relief measures and is not an immediate concern post-surgery.
D: Pink and cool fingers indicate adequate perfusion and are normal findings post-surgery.
Patients with septic shock are treated, among other drugs, with activated protein C. The purpose of this treatment is to
- A. Dampen the cytokine storm
- B. Raise the blood pressure
- C. Resolve DIC (disseminated intravascular coagulation)
- D. Boost the immune response
Correct Answer: C
Rationale: The correct answer is C: Resolve DIC. Activated protein C is used in septic shock to address the coagulopathy associated with DIC, a common complication. Activated protein C inhibits clotting factors and promotes fibrinolysis, helping to restore normal coagulation function. This treatment does not directly dampen the cytokine storm (choice A), raise blood pressure (choice B), or boost the immune response (choice D) in septic shock patients. It specifically targets the coagulation abnormalities seen in DIC, making choice C the most appropriate answer.
Select the correct statement during an allergic reaction.
- A. An allergen binds with IgE antibodies.
- B. The mast cells are deactivated.
- C. The body is immunodeficient.
- D. Helper T cells release histamine.
Correct Answer: A
Rationale: Step-by-step rationale:
1. During an allergic reaction, allergens trigger the release of IgE antibodies.
2. The allergen binds with IgE antibodies, leading to the activation of mast cells.
3. Activated mast cells release histamine and other inflammatory mediators.
4. This cascade of events causes allergic symptoms.
Therefore, option A is correct as it accurately describes the initial binding of allergen with IgE antibodies. Option B is incorrect as mast cells are activated, not deactivated. Option C is incorrect as the body is hypersensitive, not immunodeficient. Option D is incorrect as it is mast cells, not Helper T cells, that release histamine.
Which of the following immunoglobulins is present normally in plasma at the highest concentration?
- A. IgG
- B. IgM
- C. IgA
- D. IgD
Correct Answer: A
Rationale: The correct answer is A: IgG. IgG is the most abundant immunoglobulin in plasma, comprising around 75% of total immunoglobulins. It is produced in response to infections and provides long-term immunity. IgM is the first antibody produced in response to an infection, but its concentration decreases over time. IgA is mainly found in mucosal areas and secretions. IgD is present in small amounts and its function is not fully understood. Thus, IgG is the correct answer due to its high concentration in plasma and important role in long-term immunity.
What outcome would you least expect if the amount of template in a PCR fell significantly below the optimal amount?
- A. non-specific amplification
- B. increased yield
- C. Allelic drop-out (some alleles fail to amplify)
- D. Longer targets amplify poorly or fail
Correct Answer: B
Rationale: The correct answer is B: increased yield. If the amount of template in a PCR falls significantly below the optimal amount, it would be expected to result in a decreased yield rather than an increased yield. The template is essential for DNA amplification in PCR, and a lower amount would lead to fewer copies being produced. Non-specific amplification (choice A) can occur if there is too much template or incorrect primer annealing. Allelic drop-out (choice C) is likely to happen if there is insufficient template present to amplify all alleles. Longer targets amplifying poorly or failing (choice D) is also a common outcome when template concentration is low. Therefore, the least expected outcome would be an increased yield as that goes against the principle of PCR amplification.