Free systemic pathology MCQ exam model for basic medical & preclinical students

Explanation:

• Autoantibodies stimulating TSH receptor → Correct because they cause hyperthyroidism.

• Destruction of thyroid gland → Incorrect because this causes hypothyroidism.

• TSH-secreting pituitary adenoma → Incorrect because it is rare.

• Iodine deficiency → Incorrect because it causes goiter and hypothyroidism.

• Thyroid carcinoma → Incorrect because it does not cause Graves disease.

Explanation:

• Meningioma → Correct because it is the most common primary brain tumor in adults.

• Glioblastoma multiforme → Incorrect because it is the most common malignant tumor, not overall.

• Astrocytoma → Incorrect because it is less common.

• Medulloblastoma → Incorrect because it occurs in children.

• Ependymoma → Incorrect because it is relatively rare.

Explanation:

• Osteosarcoma → Correct because it is the most common malignant bone tumor in children and adolescents.

• Chondrosarcoma → Incorrect because it occurs in older adults.

• Ewing sarcoma → Incorrect because it is the second most common.

• Fibrosarcoma → Incorrect because it is rare.

• Giant cell tumor → Incorrect because it is usually benign.

Explanation:

• Bronchiectasis → Correct because it involves irreversible dilation of bronchi.

• Bronchial asthma → Incorrect because it is reversible airway obstruction.

• Chronic bronchitis → Incorrect because it involves mucus hypersecretion.

• Emphysema → Incorrect because it involves alveolar destruction.

• Pulmonary fibrosis → Incorrect because it causes restrictive lung disease.

Explanation:

• Coronary artery atherosclerosis → Correct because plaque rupture and thrombosis cause ischemia of myocardium.

• Coronary artery spasm → Incorrect because it is a less common cause.

• Congenital heart disease → Incorrect because it does not usually cause MI.

• Rheumatic heart disease → Incorrect because it affects valves.

• Infective endocarditis → Incorrect because it involves infection of endocardium

Explanation:

• Squamous cell carcinoma → Correct because it arises from ectocervical epithelium.

• Adenocarcinoma → Incorrect because it is less common.

• Leiomyosarcoma → Incorrect because it arises from smooth muscle.

• Endometrial carcinoma → Incorrect because it involves uterus, not cervix.

• Choriocarcinoma → Incorrect because it is a gestational tumor.

Explanation:

• Chronic myeloid leukemia → Correct because it shows t(9;22) BCR-ABL fusion.

• Acute lymphoblastic leukemia → Incorrect because Philadelphia chromosome is uncommon.

• Acute myeloid leukemia → Incorrect because it has different translocations.

• Chronic lymphocytic leukemia → Incorrect because it lacks this mutation.

• Hairy cell leukemia → Incorrect because it has different genetic features.

Explanation:

• Glomerular hypercellularity → Correct because inflammatory cell proliferation is characteristic.

• Tubular necrosis → Incorrect because it is seen in acute tubular necrosis.

• Crescent formation → Incorrect because it is seen in rapidly progressive GN.

• Amyloid deposition → Incorrect because it occurs in amyloidosis.

• Interstitial fibrosis → Incorrect because it is a chronic change.

Explanation:

• Duodenum → Correct because duodenal ulcers are more common than gastric ulcers.

• Esophagus → Incorrect because ulcers here are rare.

• Stomach → Incorrect because gastric ulcers are less common than duodenal.

• Jejunum → Incorrect because ulcers are uncommon here.

• Ileum → Incorrect because it is rarely affected.

Explanation:

• Hepatitis B → Correct because it is the most common cause globally.

• Alcohol → Incorrect because it is common in some regions only.

• Hepatitis C → Incorrect because it is less common worldwide than HBV.

• Non-alcoholic fatty liver disease → Incorrect because it is increasing but not the most common worldwide.

• Autoimmune hepatitis → Incorrect because it is rare.