WorksheetsCH. 1 Practice NP
Total questions: 10
Worksheet time: 10mins
A 72-year-old man is brought to the ED after sudden onset of right-sided weakness and difficulty speaking. CT confirms an acute ischemic stroke affecting the left middle cerebral artery territory. Within minutes of the vascular occlusion, neurons in the affected region begin to swell. Which pathophysiologic sequence best explains this swelling?
Prolonged ischemia causes fibrosis, reducing intracellular water content in neurons
Interruption of oxygen delivery decreases ATP production, leading to sodium-potassium pump failure, sodium influx, and osmotic water entry into neurons
Hypoxic injury accelerates DNA repair mechanisms, preventing water entry into neurons
Hypermetabolic state increases ATP production, resulting in excess potassium efflux and neuronal shrinkage
A 58-year-old woman presents for evaluation of fatigue and mild jaundice. She reports taking large doses of acetaminophen for back pain. Labs reveal elevated AST/ALT. Liver biopsy shows dilation of smooth endoplasmic reticulum in hepatocytes. Which best explains this structural change?
Increased ribosomal activity on the rough endoplasmic reticulum to produce albumin
Adaptive proliferation of smooth endoplasmic reticulum to increase detoxification of lipid-soluble compounds, including acetaminophen metabolites
Lysosomal enzyme activation to digest damaged hepatocytes and increase protein turnover
Impaired nuclear transcription resulting in reduced detoxification enzyme synthesis
A 49-year-old man with a 30-year smoking history undergoes bronchoscopy for chronic cough. Biopsy shows replacement of ciliated columnar epithelium in the bronchi with stratified squamous epithelium. Which interpretation best describes this finding and its potential consequence?
Physiologic hypertrophy increasing the strength of the airway lining and reducing airflow resistance
Pathologic metaplasia that reduces mucociliary clearance, increasing susceptibility to infection and potential progression to dysplasia and carcinoma
Compensatory hyperplasia increasing the total number of functional epithelial cells
Dysplasia indicating invasive carcinoma requiring immediate resection
A 62-year-old man with a history of hypertension is found to have left ventricular hypertrophy on echocardiogram. Which pathophysiologic explanation best accounts for the decreased exercise tolerance associated with this adaptation?
Hypertrophy allows for greater stroke volume, eliminating the need for increased oxygen during exercise
Hyperplasia increases the number of cardiac myocytes, improving contractility and perfusion
Increased muscle mass in the myocardium raises oxygen demand without a proportional increase in capillary density, leading to relative ischemia during exertion
Atrophy of cardiac myocytes limits ventricular filling and reduces preload
A 55-year-old woman develops septic shock from a urinary tract infection. Arterial blood gases show metabolic acidosis. Which cellular process best explains the acidosis in her tissues?
Shift to anaerobic glycolysis in the absence of adequate oxygen delivery, producing lactic acid that lowers intracellular pH and disrupts enzyme function
Accelerated aerobic respiration producing excess carbon dioxide
Enhanced mitochondrial oxidative phosphorylation generating reactive oxygen species
Increased nuclear DNA transcription consuming large amounts of bicarbonate
A 46-year-old man presents with a brain mass. Histology shows pleomorphic cells with large, irregular nuclei, frequent mitotic figures, and poor tissue organization. Which conclusion is most accurate?
Benign neoplasm with low metastatic potential
Malignant neoplasm characterized by loss of differentiation, rapid growth, and high likelihood of invasion and metastasis
Dysplasia confined to the epithelial layer with no invasion
Physiologic hyperplasia in response to increased demand
A patient with severe dehydration is found to have hypoperfusion-induced acute kidney injury. At the cellular level in renal tubular cells, sodium-potassium pump activity declines sharply. Which is the most direct consequence of this failure?
Increased mitochondrial ATP production preventing swelling
Accumulation of intracellular sodium, leading to osmotic influx of water, cellular swelling, and potential membrane rupture
Decreased cytoplasmic calcium concentration preventing enzyme activation
Reduced lysosomal activity limiting protein degradation
A 73-year-old man undergoes revascularization for a blocked coronary artery. Hours later, cardiac enzymes rise further, and tissue injury worsens. Which mechanism best explains this paradoxical damage?
Excess glucose utilization in aerobic metabolism causes osmotic lysis
Reperfusion generates reactive oxygen species that attack lipids, proteins, and DNA, amplifying cell injury
Hyperplasia of fibroblasts produces excessive collagen
Hypertrophy of cardiac myocytes increases oxygen demand
A 25-year-old man with Marfan syndrome is undergoing routine evaluation. Which statement best explains why his condition places him at risk for life-threatening cardiovascular events?
Overproduction of collagen in the tunica intima causes arterial narrowing
FBN1 mutation reduces fibrillin, weakening elastic fibers in the aortic wall, predisposing to aneurysm and dissection
Impaired sodium-potassium pump function increases myocardial excitability
Decreased lysosomal enzyme activity promotes vascular calcification
A patient with a history of colon polyps undergoes biopsy, revealing invasive adenocarcinoma. This represents which stage of carcinogenesis and why?
Initiation, because DNA damage has just occurred without proliferation
Promotion, because the abnormal cells are still responsive to growth signals
Progression, because the tumor cells have acquired the ability to invade beyond the basement membrane and potentially metastasize
Regression, because tumor growth has slowed
