Search results
Results From The WOW.Com Content Network
A urogenital sinus anomaly is also a rare birth defect in women where the urethra and vagina both open into a common channel. [ 3 ] [ 4 ] A persistent cloaca is a disorder where the rectum , vagina , and urinary tract meet and fuse, creating a cloaca , a single common channel.
The female reproductive system is composed of two embryological segments: the urogenital sinus and the paramesonephric ducts. The two are conjoined at the sinus tubercle. [2] [3] Paramesonephric ducts are present on the embryo of both sexes. [3] [4] Only in females do they develop into reproductive organs.
The prostate forms from the urogenital sinus and the efferent ducts form from the mesonephric tubules. For this, it is critical that the ducts are exposed to testosterone during embryogenesis. Testosterone binds to and activates androgen receptor, affecting intracellular signals and modifying the expression of numerous genes. [3]
The part of the urogenital sinus related to the bladder and urethra absorbs the ends of the Wolffian ducts and the associated ends of the renal diverticula. This gives rise to the trigone of the bladder and part of the prostatic urethra. The remainder of this part of the urogenital sinus forms the body of the bladder and part of the prostatic ...
After the separation of the rectum from the dorsal part of the cloaca, the ventral part becomes the primary urogenital sinus. [2] The urogenital sinus, in turn, divides into the superficial definitive urogenital sinus and the deeper anterior vesico-urethral portion.
As the human embryo grows and caudal folding continues, the urorectal septum divides the cloaca into a ventral urogenital sinus and dorsal anorectal canal. Before the urorectal septum has an opportunity to fuse with the cloacal membrane, the membrane ruptures, exposing the urogenital sinus and dorsal anorectal canal to the exterior.
The urogenital sinus divides into three parts, with the middle part forming the urethra; the upper part is largest and becomes the urinary bladder, and the lower part then changes depending on the biological sex of the embryo. [18]
A.—Diagram of the primitive urogenital organs in the embryo previous to sexual distinction. * 3. Ureter. * 4. Urinary bladder. * 5. Urachus. * cl. Cloaca. * cp. Elevation which becomes clitoris or penis. * i. Lower part of the intestine. * ls. Fold of integument from which the labia majora or scrotum are formed. * m, m.