Free pathophysiology MCQ exam model for basic medical & preclinical students

Explanation:

• Reduced cellular oxygen delivery → Correct because shock leads to cellular hypoxia and organ failure.

• Hypertension → Incorrect because hypotension is common.

• Adequate tissue perfusion → Incorrect because perfusion is impaired.

• Increased blood volume → Incorrect because volume may be reduced or redistributed.

• Bradycardia → Incorrect because tachycardia is common.

Explanation:

• Bronchial smooth muscle contraction → Correct because it leads to reversible airway narrowing.

• Alveolar destruction → Incorrect because it occurs in emphysema.

• Pulmonary fibrosis → Incorrect because it causes restrictive disease.

• Loss of surfactant → Incorrect because it causes alveolar collapse.

• Pleural effusion → Incorrect because it compresses lungs externally.

Explanation:

• Reduced hemoglobin concentration → Correct because oxygen-carrying capacity is decreased.

• Decreased plasma volume → Incorrect because it causes hemoconcentration.

• Increased cardiac output → Incorrect because it is a compensatory response.

• Excess iron storage → Incorrect because it does not cause hypoxia.

• Increased oxygen affinity → Incorrect because it impairs oxygen release, not carriage.

Explanation:

• Decreased cardiac output → Correct because the heart cannot meet metabolic demands.

• Increased stroke volume → Incorrect because stroke volume is reduced.

• Reduced venous return → Incorrect because venous congestion occurs.

• Enhanced myocardial contractility → Incorrect because contractility is impaired.

• Increased oxygen delivery → Incorrect because tissue hypoxia develops.

Explanation:

• Lipid accumulation and chronic inflammation → Correct because atherosclerosis involves LDL deposition and inflammatory response.

• Acute infection of arteries → Incorrect because it is not infectious.

• Autoimmune destruction of vessels → Incorrect because this occurs in vasculitis.

• Congenital absence of arteries → Incorrect because it is developmental.

• Venous thrombosis → Incorrect because it affects veins, not arteries.

Explanation:

• Activation of renin–angiotensin system → Correct because renal hypoperfusion stimulates RAAS causing vasoconstriction.

• Decreased erythropoietin → Incorrect because it causes anemia.

• Reduced sodium absorption → Incorrect because sodium retention occurs instead.

• Loss of bicarbonate → Incorrect because it causes metabolic acidosis.

• Decreased aldosterone → Incorrect because aldosterone is usually increased.

Explanation:

• Mechanisms of disease development → Correct because pathophysiology focuses on functional changes and mechanisms leading to disease.

• Structural changes in tissues → Incorrect because this is pathoanatomy.

• Normal body functions → Incorrect because this is physiology.

• Drug metabolism → Incorrect because this is pharmacology.

• Microbial classification → Incorrect because this is microbiology.

Explanation:

• Loss of bicarbonate or excess acid → Correct because it lowers blood pH metabolically.

• Increased CO₂ retention → Incorrect because it causes respiratory acidosis.

• Hyperventilation → Incorrect because it causes respiratory alkalosis.

• Decreased lactic acid → Incorrect because lactic acidosis raises acid.

• Excess bicarbonate → Incorrect because it causes metabolic alkalosis.

Explanation:

• Autoimmune destruction of beta cells → Correct because type 1 diabetes results from immune-mediated beta-cell loss.

• Insulin resistance → Incorrect because it characterizes type 2 diabetes.

• Excess glucagon secretion → Incorrect because it is secondary.

• Defective insulin receptor → Incorrect because it is rare.

• Obesity-related insulin resistance → Incorrect because it is type 2 diabetes.

Explanation:

• Pulmonary edema → Correct because left ventricular failure causes blood to back up into lungs.

• Peripheral edema → Incorrect because it is typical of right-sided failure.

• Hepatomegaly → Incorrect because it occurs in right-sided failure.

• Ascites → Incorrect because it is associated with right-sided failure.

• Jugular venous distension → Incorrect because it reflects elevated right atrial pressure.