Nokea
What is Louis Pasteur's main contribution to immunology?
- A. Development of the smallpox vaccine
- B. Discovery of phagocytosis
- C. Germ theory of disease and vaccine development
- D. Theory of innate immunity
Correct Answer: C
Rationale: Louis Pasteur's main contribution to immunology is the germ theory of disease and vaccine development. Firstly, Pasteur's germ theory revolutionized our understanding of infectious diseases by demonstrating that microorganisms are the cause. Secondly, he developed the concept of vaccination by creating vaccines for diseases such as rabies and anthrax, laying the foundation for modern immunology. The other choices are incorrect because:
A: Pasteur worked on the rabies vaccine, not the smallpox vaccine.
B: Phagocytosis was discovered by Metchnikoff, not Pasteur.
D: Pasteur did not propose the theory of innate immunity.
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A nurse caring for clients with systemic lupus erythematosus (SLE) plans care understanding the most common causes of death for these clients is which of the following? (Select one that does not apply.)
- A. Infection
- B. Cardiovascular impairment
- C. Vasculitis
- D. Chronic kidney disease
Correct Answer: C
Rationale: The correct answer is C: Vasculitis. Vasculitis is a common complication of systemic lupus erythematosus (SLE) and can lead to serious organ damage and even death. In SLE, inflammation affects blood vessels, leading to vasculitis which can cause tissue damage and impaired blood flow. While infections, cardiovascular impairment, and chronic kidney disease are also common causes of mortality in SLE patients, vasculitis is specifically associated with the disease and its complications. Infections can occur due to the immune system's weakened response, cardiovascular issues can arise from inflammation and damage to the heart and blood vessels, and chronic kidney disease can develop due to immune complex deposition in the kidneys. However, vasculitis is the most directly linked cause of death in SLE patients due to its impact on multiple organ systems.
T-cell receptors or antibodies react with antigens
- A. because both are made by lymphocytes
- B. because of complementary of molecular fit of both with antigen
- C. because both have light chain and heavy chain polypeptides
- D. cause histamine release
Correct Answer: B
Rationale: The correct answer is B because T-cell receptors and antibodies recognize antigens through complementary molecular fit. This interaction is based on the specific shape of the antigen-binding site on the receptor or antibody matching the shape of the antigen. This molecular complementarity allows for strong and specific binding between the antigen and the receptor/antibody. Choices A and C are incorrect as the presence of lymphocytes or specific polypeptide chains alone does not explain the mechanism of antigen recognition. Choice D is incorrect because histamine release is not directly related to the interaction between T-cell receptors or antibodies with antigens.
Which of the following molecular interactions mediate signal 2 during activation of naïve T cells
- A. L-Selectin/PNAD
- B. CD4/MHC II or CD8/MHC I
- C. TCR/MHC I or TCR/MHC II
- D. TCR/CD3
Correct Answer: E
Rationale: I'm sorry, but there seems to be a mistake in the question as the correct answer is not listed among the choices provided. Please provide the correct options or the correct answer so I can give you the detailed explanation you are looking for.
Patients with rheumatoid arthritis typically have pain:
- A. With activity.
- B. Upon awakening.
- C. Late in the evening.
- D. All day without remission.
Correct Answer: B
Rationale: Rheumatoid arthritis often causes morning stiffness and pain upon awakening due to inflammation and lack of movement during sleep. Pain tends to improve with activity as joints warm up.
Which of the following does not describe defensins?
- A. They disrupt pathogen membranes by penetrating them and disrupting their integrity
- B. They function as opsonins
- C. They are amphipathic, that is they have hydrophobic and hydrophilic regions
- D. They are contained in neutrophil granules
Correct Answer: B
Rationale: The correct answer is B: They function as opsonins.
Rationale:
1. Defensins disrupt pathogen membranes by penetrating them (A), not by functioning as opsonins.
2. Defensins are amphipathic (C), having hydrophobic and hydrophilic regions, which aid in membrane disruption.
3. Defensins are contained in neutrophil granules (D), contributing to their role in the immune response.
Summary:
Choice B is incorrect because defensins do not function as opsonins, which are molecules that enhance phagocytosis of pathogens by immune cells. Choices A, C, and D correctly describe aspects of defensins' mechanism of action and localization.