What is a genetic disorder that affects the lungs and digestive system, leading to thick, sticky mucus that can clog the airways?

Correct Answer: A

Rationale: The correct answer is A: Cystic fibrosis. Cystic fibrosis is a genetic disorder caused by mutations in the CFTR gene, leading to the production of thick mucus that affects the lungs and digestive system. This thick mucus can clog the airways, causing breathing difficulties and increasing the risk of lung infections. COPD (Choice B) is a different condition characterized by airflow obstruction usually due to smoking. Bronchiectasis (Choice C) is a condition where the airways are permanently widened and can also lead to mucus buildup but is not specific to the CFTR gene mutation. Pulmonary fibrosis (Choice D) is a lung disease characterized by scarring of lung tissue, not mucus buildup.

Correct Answer: A

Rationale: The correct answer is A: Pulmonary hypertension. Pulmonary hypertension refers to the condition where the walls of the arteries in the lungs become thickened and stiff, leading to increased blood pressure in the pulmonary arteries. This results in the heart having to work harder to pump blood through the lungs, causing potential damage to the heart and lungs over time. B: Pulmonary fibrosis is a condition characterized by scarring of lung tissue, not thickening and stiffening of artery walls. C: Pulmonary embolism is a blockage in one of the pulmonary arteries in your lungs, usually caused by a blood clot. It does not involve thickening and stiffening of artery walls. D: Pulmonary edema is a condition where fluid builds up in the lungs, causing difficulty in breathing. It is not related to thickened and stiffened artery walls.

Correct Answer: A

Rationale: The correct answer is A: Pneumonia. Pneumonia is an acute respiratory infection that specifically inflames the alveoli in the lungs, leading to fluid or pus accumulation. This condition can affect one or both lungs. Bronchitis (B) is inflammation of the bronchial tubes, not the alveoli. Tuberculosis (C) is a bacterial infection that primarily affects the lungs but does not always involve alveoli inflammation. Asthma (D) is a chronic respiratory condition characterized by airway inflammation and constriction, not alveoli inflammation like in pneumonia.

Correct Answer: A

Rationale: The correct answer is A: Cor pulmonale. Cor pulmonale is right-sided heart failure due to increased pressure in the pulmonary arteries, typically caused by chronic lung disease. This leads to the right side of the heart working harder to pump blood through the lungs, resulting in eventual failure. Pulmonary embolism (C) is a sudden blockage in the pulmonary artery, not a chronic condition. Heart failure (B) is a general term for when the heart is unable to pump blood effectively, not specific to the right side. Myocarditis (D) is inflammation of the heart muscle, not directly related to pulmonary hypertension.

Correct Answer: A

Rationale: The PR interval measures the time it takes for the electrical signal to travel from the atria to the ventricles, reflecting atrial depolarization and the delay at the AV node before ventricular activation. Option A is correct as it accurately describes the PR interval. Option B is incorrect as the PR interval does not measure ventricular depolarization. Option C is incorrect as the PR interval does not represent ventricular repolarization. Option D is incorrect as it describes the QT interval, not the PR interval.