Internal urethral orifice

From Wikipedia, the free encyclopedia

Internal urethral orifice
Urinary bladder
The interior of bladder.
Latin	ostium urethrae internum
Gray's	subject #255 1232
Dorlands/Elsevier	o_09/12602099

The internal urethral orifice is the opening of the urinary bladder into the urethra. It is placed at the apex of the trigonum vesicae, in the most dependent part of the bladder, and is usually somewhat crescent-shaped; the mucous membrane immediately behind it presents a slight elevation in males, the uvula vesicae, caused by the middle lobe of the prostate.

[edit] See also

• Internal sphincter muscle of urethra

[edit] External links

• Internal+urethral+orifice at eMedicine Dictionary
• SUNY Labs 44:06-0106 - "The Male Pelvis: The Urethra"

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.

v • d • e Male reproductive system Scrotum layers (skin, Dartos, External spermatic fascia, Cremaster/Cremasteric fascia, Internal spermatic fascia) • Perineal raphe • Spermatic cord Testes layers (Tunica vaginalis, Tunica albuginea, Tunica vasculosa testis) • Appendix • Mediastinum • Lobules • Septa • Leydig cell • Sertoli cell • Blood-testis barrier Spermatogenesis Spermatogonium • Spermatocytogenesis • Spermatocyte • Spermatidogenesis • Spermatid • Spermiogenesis • Spermatozoon seminal tract Seminiferous tubules (Tubuli seminiferi recti, Rete testis, Efferent ducts) • Epididymis  (Appendix, Stereocilia) • Vas deferens (Ampulla) • Ejaculatory duct urinary tract Internal urethral orifice • Urethra (Prostatic, Intermediate, Spongy, Navicular fossa) • External urethral orifice accessory glands Seminal vesicles  (Excretory duct of seminal gland) • Prostate  (Urethral crest/Seminal colliculus/Prostatic utricle/Ejaculatory duct, Prostatic sinus/Prostatic ducts) • Bulbourethral glands Penis root (Crus, Bulb, Fundiform ligament, Suspensory ligament) • body (Corpus cavernosum, Corpus spongiosum) • glans (Foreskin, Frenulum, Corona) • fascia (superficial/subcutaneous, deep/Buck's) • Tunica albuginea - Septum of the penis