snare drum definition. A shallow cylindrical drum, with wires or pieces of catgut (snares) stretched across the bottom skin to give a sharp, rattling sound when the top skin is struck. Snare drums are used in orchestras and in nearly all kinds of bands. Discover our greatest slideshows.
Although some mucins are membrane-bound due to the presence of a hydrophobic membrane-spanning domain that favors retention in the plasma membrane, most mucins are secreted onto mucosal surfaces or secreted to become a component of saliva.ature mucins are composed of two distinct regions: 1  The amino-and carboxy-terminal regions are very lightly glycosylated, but rich in cysteines. 2  A large central region formed of multiple tandem repeats of 10 to 80 residue sequences in which up to half of the amino acids are serine or threonine.
1 Various enzymes; there are three major enzymes found in saliva: 2  Î±- amylase (EC3.2.1.1), or ptyalin, secreted by the acinar cells of the parotid and submandibular glands, starts the digestion of starch before the food is even swallowed; it has a pH optimum of 7.4.roduced in salivary glands, human saliva is 99.5% water, but it contains many important substances, including electrolytes, mucus, antibacterial compounds and various enzymes.