Control of Secretion

It is not enough to know what is secreted to cause digestion... you must also understand how those secretions are controlled. For example, it is not helpful to our digestion if the stomach, pancreas, and small intestines are continually manufacturing digestive enzymes. If we have not eaten recently, those digestive enzymes may start working on the walls of our own alimentary canals! That would be very bad.

So, what regulates whether those digestive enzymes are secreted? We can talk about the following types of controls for secretion:

Chemical

	Hormones that promote or inhibit the release of digestive enzymes
	chemicals (acids, bases, or enzymes) that activate digestive enzymes

Food-related

the physical presence of food activates certain processes, most notably in the stomach

Autonomic Nervous System Control

For the first type, chemical regulation, you will work through the regulatory secretions webpage. For the second type, you will work through the control of stomach activity webpage. For the ANS control, some of it is in the regulatory secretions webpage, while more is in the food-related webpage. It should be clear as you work through these pages.