Search results
Results from the WOW.Com Content Network
The human male urethra laid open on its anterior (upper) surface. In the human male, the urethra is on average 18 to 20 centimeters (7 to 8 inches) long and opens at the end of the external urethral meatus. [10] The urethra is divided into four parts in men, named after the location: [10]
The distal section of the urethra allows a human male to direct the stream of urine by holding the penis. This flexibility allows the male to choose the posture in which to urinate. In cultures where more than a minimum of clothing is worn, the penis allows the male to urinate while standing without removing much of the clothing.
Inside the penis is the urethra, which is used to ejaculate semen and to excrete urine. Both substances exit through the meatus. When a male becomes sexually aroused, erection occurs because sinuses within the erectile tissues of the penis (corpora cavernosa and corpus spongiosum) become filled with blood.
The navicular fossa is a short dilated portion of (the spongy (or cavernous or penile) portion of) the male urethra within the glans penis just proximal to the external urethral meatus. The roof of the fossa is especially dilated, forming a lacuna; medical instruments being inserted into the male urethra should initially be directed towards the ...
The male urethra enters the penis at the superior aspect of the anterior part of the bulb (most of the bulb is thus situated inferoposteriorly to the urethra), and the arteries of bulb of penis enter near the urethra. [2] The bulb of penis is homologous to the vestibular bulbs in females. [3]
The urethra of an adult human female is 3-4 cm long. [4] The female urethra is located between the bladder neck to the external urethral orifice and is behind the symphysis pubis. [4] The urethral wall is composed of an inner epithelial lining, a sub-mucosa layer containing vascular supply, a thin fascial layer, and two layers of smooth muscle. [4]
The membranous urethra or intermediate part of male urethra is the shortest, least dilatable, and, with the exception of the urinary meatus, the narrowest part of the urethra. [citation needed] It extends from the apex of the prostate proximally to the bulb of urethra distally. It measures some 12 mm in length. It traverses the pelvic floor.
The prostatic urethra, the widest and most dilatable part of the urethra canal, is about 3 cm long.. It runs almost vertically through the prostate from its base to its apex, lying nearer its anterior than its posterior surface; the form of the canal is spindle-shaped, being wider in the middle than at either extremity, and narrowest below, where it joins the membranous portion.