Nokea
Which of the following statements is incorrect?
- A. Activation of receptors such as TLRs often precedes inflammasome formation
- B. Extracellular ATP triggers inflammasome formation
- C. Some environmental triggers, such as asbestos, can induce inflammasome formation
- D. NLRP3 is found in complex with pro-caspase 1 in resting, non-activated cells
Correct Answer: D
Rationale: The correct answer is D because NLRP3 is not found in complex with pro-caspase 1 in resting, non-activated cells. Inflammasome formation requires assembly of NLRP3 with ASC and pro-caspase 1. Choices A, B, and C are correct statements because activation of receptors like TLRs can trigger inflammasome formation, extracellular ATP can induce inflammasome formation, and environmental triggers such as asbestos can also lead to inflammasome activation.
You may also like to solve these questions
Which of the following statements is false about dendritic cells
- A. Found in tissues
- B. Are sessile cells only found in lymph nodes
- C. Express high levels of MHC molecules
- D. Best at activating naïve T cells
Correct Answer: B
Rationale: The correct answer is B because dendritic cells are not only found in lymph nodes but also in tissues. These cells are antigen-presenting cells that capture and present antigens to T cells. A, C, and D are true statements about dendritic cells: A) They are found in tissues, C) They express high levels of MHC molecules for antigen presentation, and D) They are best at activating naive T cells due to their ability to prime adaptive immune responses.
A good vaccine will:
- A. Be highly pathogenic
- B. Be highly immunogenic
- C. Induce herd immunity in a vaccinated individual
- D. All of the above
Correct Answer: B
Rationale: The correct answer is B: Be highly immunogenic. A good vaccine should effectively stimulate the immune system to produce a strong immune response against the targeted pathogen while being safe for the individual. This is crucial for developing immunity without causing harm.
Choice A (Be highly pathogenic) is incorrect because a vaccine should not cause disease or harm to the individual receiving it. Choice C (Induce herd immunity in a vaccinated individual) is also incorrect as herd immunity refers to protection of a population, not an individual.
In summary, a good vaccine should be highly immunogenic to effectively trigger an immune response without causing harm, leading to protection against the targeted pathogen.
With regard to NADPH oxidase, which of the following statements in not correct?
- A. It is the enzyme involved in the respiratory burst that follows the engagement of phagocytic receptors
- B. Individuals with mutations of NADPH oxidase subunits suffer repeated infections because of defective killing of phagocytosed pathogens
- C. It is constitutively expressed as a complex of 5 subunits in unstimulated cells
- D. It controls the formation of reactive oxygen species
Correct Answer: C
Rationale: The correct answer is C because NADPH oxidase is not constitutively expressed as a complex of 5 subunits in unstimulated cells. Instead, it is assembled and activated upon stimulation, such as during the respiratory burst following phagocytosis. Choice A is correct as NADPH oxidase is indeed involved in the respiratory burst. Choice B is correct as mutations in NADPH oxidase subunits lead to impaired pathogen killing and recurrent infections. Choice D is correct as NADPH oxidase controls the production of reactive oxygen species.
Which of the following are not typically found within secondary lymphoid tissues?
- A. naïve lymphocytes
- B. Hematopoietic stem cells
- C. Dendritic cells
- D. Antigen
Correct Answer: B
Rationale: Correct Answer: B - Hematopoietic stem cells are not typically found within secondary lymphoid tissues because they are located in the bone marrow where they give rise to various blood cells. In contrast, secondary lymphoid tissues like lymph nodes and spleen primarily consist of mature immune cells and support immune responses. Naïve lymphocytes (A), dendritic cells (C), and antigens (D) are commonly found in secondary lymphoid tissues as they play crucial roles in the immune response.
What is the medical term for an abnormal accumulation of blood in a tissue or organ?
- A. Hematoma
- B. Thrombosis
- C. Embolus
- D. Hemorrhage
Correct Answer: A
Rationale: The correct answer is A: Hematoma. A hematoma is an abnormal collection of blood within tissues. This occurs due to broken blood vessels and can lead to swelling and localized pain. Thrombosis (B) is the formation of a blood clot within a blood vessel, not an accumulation of blood in tissue. An embolus (C) is a blood clot that travels through the bloodstream and gets lodged in a blood vessel. Hemorrhage (D) refers to the excessive bleeding from blood vessels. In this case, the most appropriate term for an abnormal accumulation of blood in a tissue is hematoma.