Urethra
- The urethra is the terminal passage for urine and, in men, also carries semen.
- The urethra carries urine from bladder to outside.
- In men it also carries semen.
- It has inner-longitudinal and outer-circular smooth muscle and an external skeletal-muscle sphincter permitting voluntary closure.
- The male urethra consists of prostatic, membranous, and cavernous portions.
- The prostatic portion has transitional epithelium near the bladder and receives prostate and ejaculatory-duct secretions.
- The membranous portion passes through the urogenital diaphragm and is associated with the external sphincter.
- The cavernous portion passes through corpus-spongiosum erectile tissue and receives bulbourethral-gland secretions.
- It has transitional epithelium in the prostatic portion and pseudostratified or stratified columnar epithelium in the membranous and cavernous portions.
- The distal fossa navicularis has stratified squamous epithelium.
- Glands of Littre secrete mucus into the male urethral lamina propria.
- The female urethra is 4-5 cm long and is primarily stratified squamous epithelium with patches of pseudostratified columnar epithelium.
- It may contain glands of Littre.
Use Hide Bold Terms to cover authored terms, or Hide Every Word to cover every word in the block. Show One reveals the next hidden term or word in reading order without expanding the whole block. In Hide Main, hover a visible term to preview the full bullet.