The urethral artery arises from the internal pudendal artery a branch of the internal iliac artery. The internal pudendal artery has numerous branches including the artery of the
bulb of the penis
The bulb of penis is the proximal/posterior bulged end of the (unpaired median) corpus spongiosum penis. Together with the two crura (one crus on each side of the bulb), it constitutes the root of the penis. It is covered by the bulbospongiosus. ...
immediately before the urethral and the dorsal artery of the penis more distally.
In the male, it penetrates the perineal membrane and provides blood to the urethra and nearby erectile tissue to the glans.
[Drake, R. L., Vogl, W., Mitchell, A. W. M., & Gray, H. (2015). Gray's anatomy for students.] In the female, the urethral artery serves the analogous structures. Because the female urethra is so much shorter than the male, this structure is often impossible to find on a female cadaver.
References
Arteries of the abdomen
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