What do serous glands secrete

Small collecting ducts within salivary glands lead into larger ducts, eventually forming a single large duct that empties into the oral cavity. Most animals have three major pairs of salivary glands that differ in the type of secretion they produce:. The basis for different glands secreting saliva of differing composition can be seen by examining salivary glands histologically.

Two basic types of acinar epithelial cells exist:. Acini in the parotid glands are almost exclusively of the serous type, while those in the sublingual glands are predominantly mucus cells. In the submaxillary glands, it is common to observe acini composed of both serous and mucus epithelial cells. In the histologic sections of canine salivary gland shown above, the cells stained pink are serous cells, while the white, foamy cells are mucus-secreting cells.

Secretion of saliva is under control of the autonomic nervous system, which controls both the volume and type of saliva secreted. The dark ring you see surrounding the light areas is caused by the nuclei, which are usually darkly stained. Sublingual Salivary Gland, X Note again the mucus secretory units that appear light in the center with a dark ring around the outside. Do you see any ducts? Sublingual Salivary Gland, X The arrow bar indicates the diameter of one mucous secretory unit.

Note again the location of mucus and nucleus small arrow in the individual cells. What kind of epithelium lines the duct in the lower left part of the image? There are nine images on this page--three magnifications each of the three types of salivary glands parotid, submandibular, and sublingual.

You can see ducts and blood vessels on most slides of salivary glands. This is an enlargement of the area in the box in the image above. Sublingual Salivary Gland, 40X. The light-staining spots all over this image are clumps of mucous cells. Sublingual Salivary Gland, X. Note again the mucus secretory units that appear light in the center with a dark ring around the outside.

The arrow bar indicates the diameter of one mucous secretory unit. The submandibular gland should look to you like a cross between the other two salivary glands. Salivary glands Saliva is produced by three pairs of major salivary glands Parotid , Sublingual and Submandibular Are these exocrine glands or endocrine glands? Image B. Image C. Reveal the answers A : - Parotid gland - serous glands. B : Sublingual gland - majority of the glands are mucous secreting.

C : Submandibular gland - mixed serous and mucous glands.