Functions of Proximal Tubule in Renal Physiology Quiz

Filters blood to remove waste products and regulate electrolyte balance.

Sodium is actively reabsorbed to maintain electrolyte balance and regulate fluid volume.

Creatinine is freely filtered and not reabsorbed, making it a useful marker for kidney function.

Water moves passively across the membrane driven by osmotic gradients.

Potassium is secreted into the tubule lumen to regulate electrolyte balance.

Reabsorbs sodium and water to maintain proper fluid balance and blood pressure.

Reabsorbs bicarbonate ions to buffer blood pH and maintain acid-base balance.

Glucose is cotransported with sodium through secondary active transport mechanisms.

About two-thirds of filtered sodium is reabsorbed in the proximal tubule.

The brush border membrane primarily facilitates absorption, not filtration.

The proximal tubule primarily reabsorbs, not filters, substances from the filtrate.

ATP provides energy for active transport of ions and molecules across the tubule cells.

Aldosterone stimulates sodium reabsorption to maintain blood pressure and electrolyte balance.

Organic acids are actively transported across the tubule cells into the lumen.

Sodium can be reabsorbed passively through tight junctions between tubule cells.

Potassium ions are secreted into the tubule lumen in exchange for hydrogen ions.

Phosphate is cotransported with sodium ions into the tubule cells.