# Salivary Glands --- The **salivary glands** are [[exocrine gland|exocrine glands]] which act as [[digestive system#The Accessory Organs|accessory organs]] of the digestive system. They secrete a substance called **saliva** into the [[mouth]] during the first stages of [[digestion]]. There are two types of secretory cells in a salivary gland, [[mucous membrane|mucous cells]] and [[serous membrane|serous cells]]. Mucous cells secrete [[mucous membrane|mucin]] and serous cells secrete a watery fluid that contains [[electrolytes]] and [[amylase|salivary amylase]]. The **regulation of the salivary secretions** are located in the **salivary nuclei** in the [[brainstem]]. While most of our saliva is produced in anticipation of, or during, a meal, there is a basal level of [[parasympathetic nervous system|parasympathetic]] stimulation that keeps up a constant, low level of saliva in production to keep our oral cavity moist. The [[sympathetic nervous system]] can also activate the salivary glands in the right situation, but not very strongly, and the saliva that is produced to to sympathetic activation is sticker than the normal kind. I imagine this is why your mouth goes dry when you're nervous. ![[salivary glands.png]] There are **three different salivary glands**, each of which are slightly different in terms of where they are located and what they secrete. ## Saliva **Saliva** has many useful functions. - It contains [[amylase]] that breaks down [[digestion#Digestion of Carbohydrates|carbohydrates]]. - It contains [[lipase]] that breaks down [[digestion#Digestion of Lipids|lipids]] - It contains [[antimicrobial substances]] as well as [[antibodies]] - It allows us to [[mouth|taste]] by dissolving certain molecules - It lubricates our food when we're chewing it - It acts as a cleanser for our [[teeth]]. The salivary glands actually begin to produce saliva before food even arrives at the [[mouth]], during the **cephalic** phase of digestion. ___