What is the functional unit of the kidney?

What is the functional unit of the kidney?

• A. Nephron
• B. Glomerulus
• C. Renal Cortex
• D. Renal Pelvis

Answer: (A)

The functional unit of the kidney is the nephron. Each nephron handles the core workload: filtering blood in the glomerulus, then reabsorbing useful substances and secreting wastes as the filtrate travels through the renal tubules, ultimately forming urine. The glomerulus is the filtering component inside the nephron, but it alone does not perform all the processing—the tubules complete reabsorption and secretion. The kidney contains about a million nephrons, distributed mainly in the renal cortex, which is the outer tissue where these units reside; the renal pelvis, by contrast, is simply the urine collection area that funnels urine into the ureter.

The functional unit of the kidney is the nephron. Each nephron handles the core workload: filtering blood in the glomerulus, then reabsorbing useful substances and secreting wastes as the filtrate travels through the renal tubules, ultimately forming urine. The glomerulus is the filtering component inside the nephron, but it alone does not perform all the processing—the tubules complete reabsorption and secretion. The kidney contains about a million nephrons, distributed mainly in the renal cortex, which is the outer tissue where these units reside; the renal pelvis, by contrast, is simply the urine collection area that funnels urine into the ureter.