bild

Cur-away illustration of the salivary glands. Beneath the ear is the large parotid gland (1). The smaller submandibular gland (2) has a duct leading to the sublingual gland (3). These glands secrete saliva when stimulated by reflex reactions to the sight, smell, taste or thought of food. Saliva is an alkaline fluid that aids the swallowing of food. It contains enzymes that begin the breakdown of the starch in food. Illustration from 'Connais toi, toi meme' by Louis Figuier (1879). (KEYSTONE/SCIENCE PHOTO LIBRARY/COLLECTION ABECASIS)