Which of the following describes the pathophysiology of exercise-induced asthma?

Correct Answer: A

Rationale: The correct answer is A: 'Bronchospasm after exercise.' Exercise-induced asthma involves the narrowing of the airways (bronchospasm) triggered by physical activity. This bronchospasm leads to symptoms such as coughing, wheezing, and shortness of breath. Choices B, C, and D are incorrect because exercise-induced asthma is not primarily caused by an IgE-mediated inflammatory response to an antigen, bronchoconstriction after ingesting high-allergen foods, or increased mucus production due to a genetic mutation.

Correct Answer: A

Rationale: Polycythemia Vera, characterized by excess red blood cells, can cause tissue ischemia and necrosis due to the increased blood viscosity. This condition restricts blood flow, leading to inadequate oxygen delivery to tissues and subsequent tissue damage. Choices B, C, and D are incorrect because they are not directly associated with the pathophysiology of Polycythemia Vera.

Correct Answer: A

Rationale: Anaphylaxis is a classic example of a Type 1 hypersensitivity reaction. In Type 1 hypersensitivity, allergens trigger an immediate immune response mediated by IgE antibodies, leading to the release of histamine and other mediators. This reaction can result in symptoms ranging from mild itching and hives to severe conditions like anaphylaxis, which is a life-threatening emergency. The other options, such as indigestion (choice B), beta cell destruction (choice C), and ABO transfusion reaction (choice D), are not classified as Type 1 hypersensitivity reactions. Indigestion is typically related to gastrointestinal disturbances, beta cell destruction is associated with autoimmune conditions like type 1 diabetes, and ABO transfusion reaction involves antibodies targeting incompatible blood groups, which is a different immune mechanism compared to Type 1 hypersensitivity.

Correct Answer: B

Rationale: Atherosclerotic plaques form initially due to injury to the coronary artery endothelium, which triggers a cascade of events leading to plaque buildup. Choice A is incorrect because atherosclerotic plaques do not form due to an interruption of blood flow to the brain. Choice C is incorrect as statin medications are actually used to help lower cholesterol and reduce the risk of plaque formation. Choice D is incorrect as poor dietary modifications can contribute to atherosclerosis but are not the initial cause of plaque formation.

Correct Answer: D

Rationale: Seizures are most accurately diagnosed by EEG, which measures brain activity. Choice A is incorrect as ECG (electrocardiogram) measures heart activity, not brain activity. Choice B is incorrect as CBC (complete blood count) is a blood test and not used to diagnose seizures. Choice C is incorrect as an ECG (electrocardiogram) also measures heart activity, not brain activity, and is not the primary diagnostic tool for seizures.