Question

All of the following are characteristic of saliva except that:

stimulation of parasympathetic nervous system leads to increased flow of saliva to facilitate digestion
	its secretion is stimulated by smell of food
	its secretion is stimulated by food in the mouth
	sleep inhibits its secretion
	its secretion is inhibited by nausea

Answer 1

Ans:- e) it's secretion is inhibited my nausea.

Nausea stimulate the salivary center

As nausea cause vomiting.

Since stomach contents are highly acidic, vomiting can be quite harmful for the throat, mouth and teeth and salivating helps to reduce this by diluting and rinsing. Saliva is also weakly alkaline, which helps to neutralise acid.

a) Parasympathetic system , food ,smell of food all INCREEASEs salivation.

saliva production decreases when you sleep. This helps your body to avoid producing too much saliva that would either require you to swallow frequently during sleep, or could lead to significant fluid loss as saliva escapes from your mouth due to muscle relaxation.