Which of the following best describes the relationship between innate and adaptive immunity?
- A. Innate immunity suppresses adaptive immunity
- B. Adaptive immunity enhances innate immune functions
- C. Innate immunity activates and stimulates adaptive immunity
- D. They function entirely independently of each other
Correct Answer: C
Rationale: The correct answer is C because innate immunity plays a crucial role in initiating and influencing adaptive immunity. Innate immunity activates and stimulates adaptive immune responses by recognizing pathogens and initiating the adaptive immune system to produce specific responses. This relationship is essential for the body's overall immune defense.
Choice A is incorrect because innate immunity does not suppress adaptive immunity; instead, they work together synergistically. Choice B is incorrect because adaptive immunity does not enhance innate immune functions, but rather complements them. Choice D is incorrect because innate and adaptive immunity are interconnected and work together to provide comprehensive immune protection.
You may also like to solve these questions
A client is in the hospital and has received two doses of an angiotensin-converting enzyme for hypertension. When the nurse answers the client's call light, the client presents an appearance as shown below: What action by the nurse takes is most appropriate?
- A. Administer epinephrine 1:1000, 0.3 mg IV push immediately.
- B. Apply oxygen by facemask at 100% and a pulse oximeter.
- C. Ensure a patent airway while calling the Rapid Response Team.
- D. Reassure the client that these symptoms will go away.
Correct Answer: C
Rationale: The correct action by the nurse is to ensure a patent airway while calling the Rapid Response Team (Choice C). This is because the client is showing signs of angioedema, a potential adverse reaction to angiotensin-converting enzyme (ACE) inhibitors. Angioedema can lead to airway compromise and respiratory distress, hence ensuring a patent airway is crucial. Additionally, calling the Rapid Response Team will allow for immediate medical intervention and monitoring of the client's condition.
Choice A (Administer epinephrine) is incorrect as epinephrine is not the first-line treatment for angioedema associated with ACE inhibitors. Choice B (Apply oxygen) is not sufficient to address the potential airway compromise. Choice D (Reassure the client) is inappropriate as the client's condition requires immediate action to address the potential airway obstruction.
Which scientist is credited with introducing the germ theory of disease?
- A. Louis Pasteur
- B. Edward Jenner
- C. Elie Metchnikoff
- D. Paul Ehrlich
Correct Answer: A
Rationale: Louis Pasteur is credited with introducing the germ theory of disease. He conducted experiments that demonstrated the role of microorganisms in causing infections. He also developed pasteurization to kill harmful bacteria in food and beverages. Edward Jenner is known for developing the smallpox vaccine, not the germ theory. Elie Metchnikoff studied the immune system and phagocytosis. Paul Ehrlich is known for his work on chemotherapy and the concept of the "magic bullet," targeting specific pathogens.
Which factor is primarily responsible for the division of bacterial populations into specific zones within sediments?
- A. predation by protozoans
- B. free oxygen availability
- C. competition for suitable electron acceptors
- D. cometabolism of organic compounds
Correct Answer: B
Rationale: The correct answer is B: free oxygen availability. In sediment environments, free oxygen availability plays a crucial role in determining bacterial population distribution due to oxygen gradients. Bacteria that require oxygen will be found in aerobic zones where oxygen is present, while anaerobic bacteria will thrive in zones with limited or no oxygen. This division is primarily responsible for the spatial organization of bacterial populations within sediments.
Choice A: Predation by protozoans is not primarily responsible for division of bacterial populations within sediments as it focuses on interactions between different organisms rather than the environmental factor of oxygen availability.
Choice C: While competition for suitable electron acceptors is important for microbial communities, it is not the primary factor responsible for the division of bacterial populations within sediments.
Choice D: Cometabolism of organic compounds refers to the metabolism of compounds alongside the primary substrate, and it is not directly related to the spatial distribution of bacterial populations within sediments based on oxygen availability.
Which of the following is NOT a feature of T cells?
- A. They recognize three-dimensional structures of a pathogen
- B. Their receptors possess specificity
- C. Their receptors have one antigen-binding site
- D. Their antigen receptors are never secreted
Correct Answer: A
Rationale: The correct answer is A because T cells do not recognize three-dimensional structures of a pathogen. T cell receptors interact with processed antigen fragments presented by MHC molecules on antigen-presenting cells. Choice B is correct because T cell receptors possess specificity for antigens. Choice C is incorrect because T cell receptors have multiple antigen-binding sites. Choice D is incorrect as T cell receptors can be secreted as soluble forms.
The immunoglobulin Joining chain (J-chain) is
- A. only produced by T-Cells
- B. only produced by neutrophils
- C. associated with only multimeric forms of IgM and IgA
- D. associated with IgE for histamine release
Correct Answer: C
Rationale: Step-by-step rationale:
1. The J-chain is a polypeptide involved in the formation of polymeric IgM and IgA.
2. Polymeric forms of IgM and IgA contain the J-chain, aiding in their multimeric structure.
3. The J-chain is not exclusive to T-cells or neutrophils, making choices A and B incorrect.
4. IgE is associated with FcεRI receptors for histamine release, so choice D is incorrect.
Summary:
The correct answer is C because the J-chain is specifically associated with the multimeric forms of IgM and IgA, helping to form their structure. Choices A, B, and D are incorrect as the J-chain is not solely produced by T-cells, neutrophils, or associated with IgE for histamine release.