The cell membrane, therefore, has two functions: first, to be a barrier keeping the constituents of the cell in and unwanted substances out and, second, to be a gate allowing transport into the cell of essential nutrients and movement from the cell of waste products. 1
Magnesium can affect muscle relaxation through direct action on cell membranes. Mg2+ ions close certain types of calcium channels, which conduct positively charged calcium ions into neurons. With an excess of magnesium, more channels will be blocked and nerve cells activity will decrease.2
- Cell membrane | Definition, Function, & Structure | Britannica – https://www.britannica.com/science/cell-membrane
- https://en.wikipedia.org/wiki/Magnesium_in_biology