Is my explanation correct?

1.

Excess water in the mucus triggers detection by epithelial cell membrane.

2.

Carrier proteins in basal membranes actively pump sodium ions out of the cell, creating a concentration gradient.

3.

Sodium ions diffuse into the epithelial cell via sodium ion channels.

4.

Increased sodium ions in tissue fluid create an electrical gradient between tissue fluid and mucus.

5.

Negatively charged chloride ions diffuse out of the mucus into tissue fluid through gaps between epithelial cells, driven by the electrical gradient.