Final answer:
The primary role of the nephron is to eliminate nitrogenous wastes and help regulate the volume, composition, and pH of the blood through filtration, reabsorption, and secretion. so, option 2 is the correct answer.
Step-by-step explanation:
The primary role of the nephron in urine formation is to eliminate nitrogenous wastes and regulate volume, composition, and pH of the blood. Nephrons are responsible for carrying out these tasks through three principal functions: filtration, reabsorption, and secretion. During filtration, blood plasma is filtered in the glomerulus, allowing water and small molecules to enter Bowman's capsule. Reabsorption involves the movement of essential substances from the nephron back into the blood, while secretion adds additional wastes into the forming urine. Additionally, nephrons contribute to various other functions, such as regulating blood pressure through the production of renin, red blood cell production through erythropoietin (EPO), and calcium absorption through the conversion of calcidiol into calcitriol.
The primary role of the nephron in urine formation is to eliminate nitrogenous wastes and regulate volume, composition, and pH of the blood.
Nephrons accomplish this through three principle functions: filtration, reabsorption, and secretion. Filtration occurs in the glomerulus, where fluids, electrolytes, and molecules from the blood pass into the nephron. Reabsorption involves the movement of nutrients and most water back into the blood, while secretion adds additional wastes and helps maintain homeostatic pH.
Additionally, nephrons have secondary functions that impact blood pressure, red blood cell production, and calcium absorption.