- Smooth muscle
- One of the three types of muscle tissue in the body (skeletal, smooth, cardiac). Generally forms the supporting tissue of blood vessels and hollow internal organs such as the stomach, intestine, and bladder. So named because of the absence of microscopic lines called "cross-striations" which are seen in the other two types.
* * *smooth muscle n muscle tissue that lacks cross striations, that is made up of elongated spindle-shaped cells having a central nucleus, and that is found esp. in vertebrate hollow organs and structures (as the small intestine and bladder) as thin sheets performing functions not subject to direct voluntary control and in all or most of the musculature of invertebrates other than arthropods called also nonstriated muscle, unstriated muscle compare CARDIAC MUSCLE, STRIATED MUSCLE
* * *muscle that produces slow long-term contractions of which the individual is unaware. Smooth muscle occurs in hollow organs, such as the stomach, intestine, blood vessels, and bladder. It consists of spindle-shaped cells within a network of connective tissue and is under the control of the autonomic nervous system. Compare striated muscle.
* * *smooth involuntary muscle a type of muscle without transverse striations in its constituent fibers; it is found in the walls of the viscera and blood vessels and in the dermis and is not under voluntary control. See muscle and see Plate 32.
Medical dictionary. 2011.
Look at other dictionaries:
Smooth muscle — is a type of non striated muscle, found within the tunica media layer of large and small arteries and veins, the bladder, uterus, male and female reproductive tracts, gastrointestinal tract, respiratory tract, the ciliary muscle, and iris of the… … Wikipedia
smooth muscle — Muscle tissue in vertebrates made up from long tapering cells that may be anything from 20 500 m m long. Smooth muscle is generally involuntary, and differs from striated muscle in the much higher actin/myosin ratio, the absence of conspicuous… … Dictionary of molecular biology
smooth muscle — n. a contractile type of muscle tissue controlled by the involuntary nervous system, occurring in the walls of the uterus, stomach, intestines, blood vessels, etc., and characterized by nonstriated, spindle shaped cells … English World dictionary
smooth muscle — noun 1. a muscle that contracts without conscious control and found in walls of internal organs such as stomach and intestine and bladder and blood vessels (excluding the heart) • Syn: ↑involuntary muscle • Hypernyms: ↑muscle, ↑musculus •… … Useful english dictionary
smooth muscle — Anat. involuntary muscle tissue in the walls of viscera and blood vessels, consisting of nonstriated, spindle shaped cells. [1885 90] * * * ▪ anatomy also called involuntary muscle muscle that shows no cross stripes under microscopic… … Universalium
smooth muscle — involuntary muscle muscle that produces slow long term contractions of which the individual is unaware. Smooth muscle occurs in hollow organs, such as the stomach, intestine, blood vessels, and bladder. It consists of spindle shaped cells within… … The new mediacal dictionary
smooth muscle — smooth′ mus′cle n. anat. involuntary muscle tissue in the walls of viscera and blood vessels, consisting of nonstriated, spindle shaped cells … From formal English to slang
smooth muscle — noun Date: circa 1890 muscle tissue that lacks cross striations, is made up of elongated spindle shaped cells having a central nucleus, and is found especially in vertebrate hollow organs and structures (as the digestive tract and bladder) as… … New Collegiate Dictionary
smooth muscle — noun Physiology muscle tissue in which the contractile fibrils are not highly ordered, occurring in the gut and other internal organs and not under voluntary control. Often contrasted with striated muscle … English new terms dictionary
smooth muscle — noun Involuntary muscle which is found within the intestines, throat, uterus, and blood vessel walls … Wiktionary