Nokea
What are the key steps of phagocytosis?
- A. Recognition, digestion, and excretion
- B. Recognition, ingestion, and digestion
- C. Adhesion, secretion, and ingestion
- D. Activation, release, and excretion
Correct Answer: B
Rationale: The correct answer is B: Recognition, ingestion, and digestion. Firstly, recognition is essential for phagocytes to identify and bind to the target. Next, ingestion involves engulfing the target into a phagosome. Finally, digestion occurs within the phagolysosome, where enzymes break down the target. Choices A, C, and D are incorrect because they do not accurately represent the sequential key steps of phagocytosis.
You may also like to solve these questions
What is the role of complement component C3b in immune responses?
- A. Initiates MAC formation
- B. Acts as an opsonin to enhance phagocytosis
- C. Triggers inflammation
- D. Neutralizes cytokines
Correct Answer: B
Rationale: The correct answer is B: C3b acts as an opsonin to enhance phagocytosis. C3b binds to pathogens and enhances their recognition by phagocytic cells, facilitating their engulfment and destruction. This process is crucial for efficient immune responses. A, MAC formation, is initiated by the membrane attack complex, not C3b. C, inflammation, is triggered by various mediators such as histamine and cytokines, not C3b. D, neutralizing cytokines, is not a function of C3b; cytokines are regulatory proteins involved in immune responses.
According to the hygiene hypothesis, which of the following factors protect us from developing immune diseases?
- A. Small family size
- B. Good sanitation
- C. Low antibiotic use
- D. Living in "westernized" countries
Correct Answer: C
Rationale: The correct answer is C: Low antibiotic use. The hygiene hypothesis suggests that reduced exposure to infections, which can happen with low antibiotic use, can lead to an increased risk of immune diseases. Antibiotics can disrupt the balance of gut microbiota, which plays a crucial role in immune system development. A: Small family size may not necessarily protect against immune diseases as it does not directly relate to exposure to infections. B: Good sanitation can reduce the spread of infections but may not necessarily protect against immune diseases. D: Living in "westernized" countries is a broad factor and does not directly address the impact of low antibiotic use on immune diseases.
A 28-year-old male Gulf War veteran tells the nurse he gets a headache, sore throat, shortness of breath, and nausea when his girlfriend wears perfume and when he was painting her apartment. He is afraid he has cancer. What does the nurse suspect may be the patient’s problem?
- A. He has posttraumatic stress disorder.
- B. He has multiple chemical sensitivities.
- C. He needs to wear a mask when he paints.
- D. He is looking for an excuse to break up with his girlfriend.
Correct Answer: B
Rationale: Multiple chemical sensitivities could explain the patient's symptoms triggered by exposure to various chemicals.
When the clinic nurse starts to take the "air cast" off the grade 2 sprain, the patient asks why it is being removed since he still has pain. Which explanation is best?
- A. "Long-term immobilization can interfere with adequate circulation."
- B. "Long-term immobilization may increase long-term edema."
- C. "Long-term immobilization can cause permanent disability."
- D. "This cast will be replaced with a heavier cast."
Correct Answer: C
Rationale: The correct answer is C because long-term immobilization can indeed cause permanent disability in the case of a grade 2 sprain. Prolonged immobilization can lead to muscle atrophy, joint stiffness, and decreased range of motion, which can result in long-term disability. Choice A is incorrect because adequate circulation is more related to prolonged immobilization, not short-term removal for evaluation. Choice B is incorrect as edema is a short-term concern and not a direct result of long-term immobilization. Choice D is incorrect as there is no indication that a heavier cast will be used.
A major effector function of TH2 cells is:
- A. Protection against intracellular bacteria
- B. Protection against parasitic worms
- C. Regulation of the adaptive immune response through the secretion of anti-inflammatory cytokines
- D. Activation of macrophages
Correct Answer: B
Rationale: The correct answer is B because TH2 cells play a crucial role in protecting against parasitic worms by secreting cytokines that promote eosinophil activation and antibody production. This response helps to expel the parasites from the body.
Incorrect choices:
A: TH1 cells are responsible for protection against intracellular bacteria.
C: TH3 cells, not TH2 cells, are known for secreting anti-inflammatory cytokines.
D: Activation of macrophages is primarily mediated by TH1 cells through IFN-gamma secretion.