The protein x is only detectable inside the glial cells. Why is protein x not also detected in the extracellular fluid?

Answer;

The glial cell membrane is not permeable to protein X, and is not actively transported out of the cell.

Explanation;

-The glial cells surround neurons and provide support for and insulation between them. Glial cells are the most abundant cell types in the central nervous system. Types of glial cells include oligodendrocytes, astrocytes, ependymal cells, Schwann cells, microglia, and satellite cells.

- If protein x is only detectable inside the glial cells and not detected in the extracellular fluid, it means that the glial cell membrane is not permeable to protein X, and is not actively transported out of the cell.