Nokea
Who introduced the concept of discrimination between self and non-self?
- A. Elie Metchnikoff
- B. Louis Pasteur
- C. Paul Ehrlich
- D. Charles Janeway
Correct Answer: C
Rationale: Paul Ehrlich introduced the concept of discrimination between self and non-self through his "horror autotoxicus" theory. He proposed that the immune system can differentiate between harmful non-self antigens and self-antigens. Ehrlich's theory laid the foundation for understanding immune responses and the development of immunology. Metchnikoff focused on phagocytosis, Pasteur on microbiology, and Janeway on innate immunity, not specifically on self vs. non-self discrimination.
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What is the medical term for the breakdown of red blood cells?
- A. Leukocytosis
- B. Thrombocytosis
- C. Hemolysis
- D. Anemia
Correct Answer: C
Rationale: The correct answer is C: Hemolysis. Hemolysis is the medical term for the breakdown of red blood cells. This process releases hemoglobin and other components into the bloodstream. Leukocytosis (A) is an increase in white blood cells, thrombocytosis (B) is an increase in platelets, and anemia (D) is a decrease in red blood cells or hemoglobin levels. In this context, hemolysis specifically refers to the breakdown of red blood cells, making it the correct answer.
Adding adjuvants in Flu vaccines, such as AS03 used in Canada in the 2009 H1N1 vaccine is thought to
- A. Induce danger signals
- B. Generally boost the innate immune response
- C. Create a slower release of antigen (antigen depot)
- D. All of the above is correct
Correct Answer: D
Rationale: Step 1: Adjuvants like AS03 induce danger signals by activating innate immunity, enhancing the response to the vaccine.
Step 2: Adjuvants generally boost the innate immune response by increasing antigen presentation and cytokine production.
Step 3: Adjuvants create a slower release of antigen, forming an antigen depot which prolongs immune stimulation.
Summary: Choice D is correct because adjuvants like AS03 do induce danger signals, boost the innate immune response, and create a slower release of antigen, leading to enhanced vaccine efficacy. Choices A, B, and C are incorrect as they do not encompass all the effects of adjuvants in flu vaccines.
How many Toll-like receptors (TLRs) are found in humans?
- A. 5
- B. 8
- C. 10
- D. 12
Correct Answer: C
Rationale: The correct answer is C: 10. Toll-like receptors (TLRs) are a family of proteins involved in the innate immune response. In humans, there are 10 known TLRs that recognize different pathogen-associated molecular patterns. Each TLR is specific to different types of pathogens, allowing for a diverse recognition and response system. Therefore, the correct answer is 10. Choices A, B, and D are incorrect because they do not match the known number of TLRs in humans, which is 10.
Which symptom is NOT typically associated with anaphylaxis?
- A. Sudden drop in blood pressure
- B. Massive edema
- C. Severe bronchoconstriction
- D. T cell apoptosis
Correct Answer: D
Rationale: The correct answer is D: T cell apoptosis. Anaphylaxis is a severe allergic reaction that involves a rapid immune response. T cell apoptosis is not a typical symptom of anaphylaxis.
Rationale:
1. A: Sudden drop in blood pressure is associated with anaphylaxis due to systemic vasodilation.
2. B: Massive edema is common in anaphylaxis due to increased vascular permeability.
3. C: Severe bronchoconstriction is a hallmark of anaphylaxis, leading to respiratory distress.
4. D: T cell apoptosis is not a characteristic feature of anaphylaxis. T cells play a role in adaptive immunity, not the immediate hypersensitivity reaction seen in anaphylaxis.
Summary:
T cell apoptosis is not typically associated with anaphylaxis, unlike the other symptoms listed which are common manifestations of this severe allergic reaction.
Which of the following are not found in Cyanobacteria?
- A. thylakoids
- B. gas vesicles
- C. chloroplasts
- D. heterocysts
Correct Answer: C
Rationale: The correct answer is C: chloroplasts. Cyanobacteria do not have chloroplasts because they are prokaryotic organisms and do not possess membrane-bound organelles like chloroplasts found in eukaryotic cells. Instead, they perform photosynthesis using thylakoids, which are membrane-bound compartments where photosynthesis occurs. Gas vesicles are also present in cyanobacteria and help regulate their buoyancy. Heterocysts are specialized cells that aid in nitrogen fixation, a process that allows cyanobacteria to convert atmospheric nitrogen into a form that can be used by the organism. Therefore, the absence of chloroplasts in cyanobacteria makes choice C the correct answer.