Biomaterial Database

Embryology of the lower genitourinary tract. 1978

F F Marshall

The urinary and genital systems are closely related in their development so that dividing them into separate divisions is often artificial. The lower urinary system begins as a cloaca. The urorectal septum then divides the cloaca into a ventral urogenital sinus and a dorsal hindgut. The ureteral bud forms off the mesonephric duct. The male and female genital systems are the same until the gonad assumes characteristics of the testis or ovary in the eighth week of gestation. It is not until the eleventh or twelfth week that the external genitalia assume specific sexual characteristics. Anomalies of the urethra and bladder can vary from a severe epispadias-exstrophy complex to a minimal Type I urethral valve. Ureteral anomalies include duplications, ectopia, and ureteroceles. An undescended testis is probably the most common anomaly in the male genital tract. Female genital anomalies can include a variety of uterine duplication anomalies. Gonadal abnormalities are often created by a chromosomal defect and are ultimately reflected by abnormal sexual differentiation.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D001743	Urinary Bladder	A musculomembranous sac along the URINARY TRACT. URINE flows from the KIDNEYS into the bladder via the ureters (URETER), and is held there until URINATION.	Bladder,Bladder Detrusor Muscle,Detrusor Urinae,Bladder Detrusor Muscles,Bladder, Urinary,Detrusor Muscle, Bladder,Detrusor Muscles, Bladder
D002988	Cloaca	A dilated cavity extended caudally from the hindgut. In adult birds, reptiles, amphibians, and many fishes but few mammals, cloaca is a common chamber into which the digestive, urinary and reproductive tracts discharge their contents. In most mammals, cloaca gives rise to LARGE INTESTINE; URINARY BLADDER; and GENITALIA.	Cloacas
D005260	Female		Females
D005836	Genitalia, Female	The female reproductive organs. The external organs include the VULVA; BARTHOLIN'S GLANDS; and CLITORIS. The internal organs include the VAGINA; UTERUS; OVARY; and FALLOPIAN TUBES.	Accessory Sex Organs, Female,Sex Organs, Accessory, Female,Genital Organs, Female,Genitals, Female,Reproductive System, Female,Female Genital,Female Genital Organ,Female Genital Organs,Female Genitalia,Female Genitals,Female Reproductive System,Female Reproductive Systems,Genital Organ, Female,Genital, Female,Reproductive Systems, Female
D005837	Genitalia, Male	The male reproductive organs. They are divided into the external organs (PENIS; SCROTUM; and URETHRA) and the internal organs (TESTIS; EPIDIDYMIS; VAS DEFERENS; SEMINAL VESICLES; EJACULATORY DUCTS; PROSTATE; and BULBOURETHRAL GLANDS).	Accessory Sex Organs, Male,Genital Organs, Male,Sex Organs, Accessory, Male,Genitals, Male,Reproductive System, Male,Genital, Male,Male Genital,Male Genital Organs,Male Genitalia,Male Genitals,Male Reproductive System,Male Reproductive Systems,Reproductive Systems, Male
D006066	Gonads	The gamete-producing glands, OVARY or TESTIS.	Gonad
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D014513	Ureter	One of a pair of thick-walled tubes that transports urine from the KIDNEY PELVIS to the URINARY BLADDER.	Ureters
D014521	Urethra	A tube that transports URINE from the URINARY BLADDER to the outside of the body in both the sexes. It also has a reproductive function in the male by providing a passage for SPERM.	External Urethral Sphincter,External Urinary Sphincter,Internal Urethral Sphincter,Internal Urinary Sphincter,Internal Vesical Sphincter,Urethral Sphincters,External Urethral Sphincters,External Urinary Sphincters,Internal Urethral Sphincters,Internal Urinary Sphincters,Internal Vesical Sphincters,Sphincter, External Urethral,Sphincter, External Urinary,Sphincter, Internal Urethral,Sphincter, Internal Urinary,Sphincter, Internal Vesical,Sphincter, Urethral,Urethral Sphincter,Urethral Sphincter, External,Urethras,Urinary Sphincter, External,Urinary Sphincter, Internal,Vesical Sphincter, Internal