Na+ is co-transported with which of the following substances?

Sodium ions (Na+) are co-transported with glucose in a process known as secondary active transport. This means that the movement of Na+ down its concentration gradient is coupled with the transport of glucose against its concentration gradient. This co-transport mechanism occurs primarily in the intestinal epithelium and in the renal tubules, where Na+ is first transported out of the cells, creating a concentration gradient. When sodium enters the cell through a co-transporter protein, glucose can hitch a ride along with it, allowing for its absorption into the cell.

The coupling of these two substances is essential for maximizing nutrient absorption, especially in the digestive system, where glucose needs to be efficiently taken up from the intestinal lumen into the bloodstream. Sodium-glucose co-transporters (SGLT) facilitate this process, enabling the body to utilize glucose effectively as a primary energy source.