The nurse is caring for a college student who has reported periods of rapid heart rate and palpitations immediately prior to an important examination. The nurse is aware that these changes are likely due to which of the following?

Correct Answer: B

Rationale: Rapid heart rate and palpitations before an exam are due to the sympathetic nervous system’s stress response, releasing adrenaline to increase heart rate. The parasympathetic system slows heart rate, and the other options are less directly related to acute stress.

Correct Answer: B

Rationale: Plasma proteins (albumin, globulins, fibrinogen) are ~7-9% of plasma volume; water is ~91-93%, and solutes (e.g., electrolytes) make up the rest. Higher percentages reflect whole blood or other components.

Correct Answer: B

Rationale: Glomerular capillary pressure is higher (~55 mmHg) than in systemic capillaries (~25 mmHg) due to the afferent arteriole’s larger diameter and efferent arteriole’s resistance, enhancing filtration for urine formation. Lower pressure (A) is typical elsewhere.

Correct Answer: D

Rationale: Systemic circulation involves blood flow from the heart to the body (excluding lungs) and back, including the aorta (A), femoral vein (B), and superior vena cava (C). The pulmonary vein (D) belongs to pulmonary circulation, carrying oxygenated blood from lungs to the left atrium, making it the exception.

Correct Answer: A

Rationale: The right atrium receives deoxygenated blood from the body via the superior vena cava, inferior vena cava, and coronary sinus (A, drains heart muscle). Pulmonary veins (B, D) return oxygenated blood to the left atrium, and pulmonary arteries (C) carry blood from the right ventricle to lungs.