Sphincter

From Wikinfo

[[es:esf�nter]][[de:Schlie�muskel]]

From late Latin sphincter, from Greek sphinkter, band, contractile muscle, from sphingein, to bind tight.

A sphincter is a ring-like muscle that normally maintains constriction of a natural body passage or orifice and that relaxes as required by normal physiological functioning.

Some examples of sphincters include:

• Anus
• Cardia
• Urethral sphincter

References

• Adapted from the Wikipedia article, "Sphincter" http://en.wikipedia.org/wiki/Sphincter December 27, 2003