How does filtered glucose enter and leave a proximal convoluted tubule (PCT) cell?

Explanation

**Step-by-Step Solution:**

1. **Understanding the Proximal Convoluted Tubule (PCT):**
- The PCT is the first segment of the nephron after the Bowman's capsule. It plays a crucial role in the reabsorption of various substances, including glucose, from the filtrate back into the bloodstream.

2. **Entry of Glucose into PCT Cells:**
- Glucose enters the PCT cells primarily through a mechanism known as sodium-glucose symport. This process involves a sodium-glucose symporter protein located in the cell membrane of the PCT.
- The sodium-glucose symporter utilizes the sodium gradient established by the Na+/K+ ATPase pump. As sodium ions (Na+) move into the cell down their concentration gradient, glucose is co-transported into the cell against its concentration gradient.
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