How is saliva so readily produced? Do we just have reservoirs of water in storage somewhere in our head?

Question

How is saliva so readily produced? Do we just have reservoirs of water in storage somewhere in our head?

In: 418

Answer 1

Reservoirs? Not really. Pipes? Yes. The “water” for saliva comes from your blood.

Saliva is made by the salivary glands. The cells in these glands pump out saliva through their membranes. This depletes the amount of water inside themselves, but they’re constantly replenishing themselves by taking water from your bloodstream.

Note that “pumping fluid out through their membranes” sounds pretty obvious, but it’s actually an important distinction. A lot of other glands in your body don’t work that way – they secrete fluid by either partially or fully self-destructing like microscopic water balloons.