Final Answer:
The cell that helps the ascending limb reabsorb Na+ and Cl- in the renal tubule is the thick ascending limb cell.
Step-by-step explanation:
The renal tubule is a key component of the nephron, the functional unit of the kidney responsible for urine formation. The thick ascending limb of the loop of Henle is involved in the reabsorption of sodium ions (Na+) and chloride ions (Cl-) from the filtrate. Specialized cells in this segment actively transport these ions from the tubular fluid into the interstitial space. This reabsorption is crucial for maintaining the osmotic gradient in the kidney, facilitating the concentration of urine. The thick ascending limb cells use the Na+-K+-2Cl- cotransporter to transport these ions across the tubular epithelium.