Tube that connects the urinary bladder to the external urethral orifice
Not to be confused with
ureter .
The urethra (pl. : urethras or urethrae ) is the tube that connects the urinary bladder to the urinary meatus ,[ 1] [ 2] through which placental mammals urinate and ejaculate .[ 3] In non-mammalian vertebrates , the urethra also transports semen but is separate from the urinary tract.[ 4]
The external urethral sphincter is a striated muscle that allows voluntary control over urination.[ 5] The internal sphincter , formed by the involuntary smooth muscles lining the bladder neck and urethra, receives its nerve supply by the sympathetic division of the autonomic nervous system .[ 6] The internal sphincter is present both in males and females.[ 7] [ 8] [ 9]
^ Brading, Alison F. (January 1999). "The physiology of the mammalian urinary outflow tract" . Experimental Physiology . 84 (1): 215– 221. doi :10.1111/j.1469-445X.1999.tb00084.x . ISSN 0958-0670 . PMID 10081719 .
^ Lombardi, Julian (2012-12-06). Comparative Vertebrate Reproduction . Springer Science & Business Media. ISBN 978-1-4615-4937-6 .
^ Marvalee H. Wake (15 September 1992). Hyman's Comparative Vertebrate Anatomy . University of Chicago Press. pp. 583–. ISBN 978-0-226-87013-7 . Retrieved 6 May 2013 .
^ Todd, Robert Bentley (1852). The Cyclopaedia of Anatomy and Physiology . Sherwood.
^ Legato, Marianne J.; Bilezikian, John P., eds. (2004). "109: The Evaluation and Treatment of Urinary Incontinence". Principles of Gender-specific Medicine . Vol. 1. Gulf Professional Publishing. p. 1187.
^ Chancellor, Michael B; Yoshimura, Naoki (2004). "Neurophysiology of Stress Urinary Incontinence" . Reviews in Urology . 6 (Suppl 3): S19 – S28 . PMC 1472861 . PMID 16985861 .
^ Jung, Junyang; Anh, Hyo Kwang; Huh, Youngbuhm (September 2012). "Clinical and Functional Anatomy of the Urethral Sphincter" . International Neurourology Journal . 16 (3): 102– 106. doi :10.5213/inj.2012.16.3.102 . PMC 3469827 . PMID 23094214 .
^ Karam, I.; Moudouni, S.; Droupy, S.; Abd-Almasad, I.; Uhl, J. F.; Delmas, V. (April 2005). "The structure and innervation of the male urethra: histological and immunohistochemical studies with three-dimensional reconstruction" . Journal of Anatomy . 206 (4): 395– 403. doi :10.1111/j.1469-7580.2005.00402.x . PMC 1571491 . PMID 15817107 .
^ Ashton-Miller, J. A.; DeLancey, J. O. (April 2007). "Functional anatomy of the female pelvic floor" . Annals of the New York Academy of Sciences . 1101 (1): 266– 296. Bibcode :2007NYASA1101..266A . doi :10.1196/annals.1389.034 . hdl :2027.42/72597 . PMID 17416924 . S2CID 6310287 . Archived from the original on Aug 22, 2023 – via Deep Blue Documents.