Question 1

Nephrons are the functional units of the kidney.

Nephrons are the essential structural and functional units of the kidney responsible for filtering blood and forming urine. Each nephron consists of various components that work together to regulate water and electrolyte balance, making them crucial for kidney function.

A) Ureters

Ureters are the tubes that transport urine from the kidneys to the bladder, but they do not play a role in the filtration or urine formation processes. Therefore, they are not considered functional units of the kidney.

B) Glomeruli

Glomeruli are a part of the nephron and serve as the filtration units within the kidney. However, they alone do not encompass the entire functional unit of the kidney, which is the nephron itself. Thus, while glomeruli are important, they are not the complete answer.

C) Nephrons

Nephrons are the functional units of the kidney, consisting of glomeruli, tubules, and other structures that work in unison to filter blood, reabsorb necessary substances, and excrete waste as urine. This comprehensive role confirms nephrons as the core functional units of kidney operations.

D) Renal capsules

Renal capsules, which surround the kidneys, provide protection and structural support. However, they do not participate in the kidney's functional processes, such as filtration or urine production, making them irrelevant when identifying the functional units of the kidney.

Conclusion

Nephrons are definitively the functional units of the kidney, as they encompass all necessary components for blood filtration and urine formation. Other options, like ureters and renal capsules, serve different purposes unrelated to the core functions of the kidney, while glomeruli, though essential, are just one part of the nephron. Therefore, option C is the only correct choice.