Correct Answer: C

Rationale: The correct answer is C: Too much dopamine in the brain. Parkinson's disease is characterized by a deficiency of dopamine in the brain, not an excess. This deficiency leads to the motor symptoms associated with the disease. Choices A, B, and D are incorrect. Mobility and functioning are affected in Parkinson's disease due to the lack of dopamine, not an excess. The liver and kidneys are not directly related to Parkinson's disease. Skeletal muscle flaccidity is not typically a primary symptom of Parkinson's disease, which is more characterized by rigidity and tremors.

Correct Answer: C

Rationale: A tension pneumothorax is characterized by a large accumulation of trapped air in the pleural space, creating pressure that affects both the lungs and heart. This condition can lead to life-threatening consequences by shifting mediastinal structures and impairing cardiac function. Treatment involves decompressing the trapped air to relieve the tension. Choices A, B, and D are incorrect as they do not describe the primary pathophysiological mechanism of tension pneumothorax, which is the accumulation of air in the pleural space, not blood, rib fractures, or alveolar fluid accumulation.

Correct Answer: D

Rationale: Atherosclerotic plaques form in the body due to injury to the endothelium of the coronary arteries. When the endothelium is damaged, it triggers an inflammatory response that leads to the accumulation of fats, cholesterol, and other substances, forming plaques. These plaques can narrow the arteries, reducing blood flow and potentially leading to serious complications like heart attacks or strokes. Poor dietary habits (choice A) can contribute to the development of atherosclerosis by promoting the buildup of plaque-forming substances in the blood, but the direct cause is the injury to the endothelium. Administration of statin medication (choice B) is actually a treatment for high cholesterol and aims to reduce the risk of plaque formation. Interruption of blood flow to the brain (choice C) is more related to conditions like ischemic stroke rather than the primary cause of atherosclerotic plaque formation.

Correct Answer: A

Rationale: Vascular spasm is the initial step in hemostasis, where blood vessels constrict to reduce blood flow to the injured area. This constriction helps limit blood loss until further steps like platelet plug formation and coagulation can take place. Platelet plug formation and coagulation occur after the vascular spasm, making them incorrect choices. Dissolution of the clot happens much later in the healing process, after the injury has sufficiently healed.

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.