Stromatolite. A rock-like mound often in fossil form, created by blue-green algae.

Structural Gene. See Operon

Structureless Lamella Mesogloea.

Style. Prolongation of carpel supporting stigma

Subcutaneous. Immediately below dermis of vertebrates skin. S. tissue is usually loose connective tissue, which may contain much fat (see Blubber, Fascia) and in many tetrapods a sheet of stripted muscle (panniculus carnosus conspicuous in some mammals) which can move th skin or its scales.

Suberin. Complex mixture of oxidation and concentration products of the fatty acids; present in walls of cork cells rendering them impervious to water.

Suberization. Deposition of suberin.

Subfamily. A taxon immediately below the level of family and above genus.

Subulate. Long narrow and pointed.

Succession. Progressive change in composition of a community of organisms towards a largely stable climax; e.g. from initial colonization of a bare area.

Sucrose. Cane sugar. A disaccharide (with twelve carbon atoms) widespread in plants, but not in animals. And not in mammalian body, except in food in gut. It is a compound of a glucose and fructose.

Suspensor. (1) In phycomycete fungi of the order Mucorales, cell supporting a gametangium (2) In seed plants and in a few pteridophytes, structure developing from fertilized egg-cell along with the embryo, and bearing latter at its apex. By elongation of suspensor embryo is carried into nutritive endosperms or prothallus tissue.

Suture. The line marking the junction of two body structures. Examples are the immovable joints between the bones of the skull nd, in plants, the seam along the edge of a pea or bean pod.

Sweat gland. A small gland in mammalian skin that secretes sweat. The distribution of sweat glands on the body surface varies between species; they occur over most of the body surface in man and higher primates but have a more restricted distribution in other mammals.