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What is Length of the male adult urethra is - and explain in detail?
Urethra
-        Length
o   Male - 20 cms
o   Female - 4 cms
-        Shortest part of the male urethra- Membranous part
-        The longest part of the male urethra- Penile urethra
-        Location of sphincter urethrae- Membranous part
-        Prostatic urethra
o   Widest part
o   Most dilatable part
o   Concave anteriorly.
o   Route- downwards & forwards. Exit prostate slightly anterior to its apex.
o   Crescentic on the cross section
o    Structures on the posterior wall
§  Urethral crest
§  Colliculus seminalis (verumontanum)
§  Opening of ejaculatory ducts
§  Prostatic sinuses with the opening of prostate glands
o   Lymphatics
§  Membranous part- Internal iliac nodes
§  Prostatic part- Internal iliac nodes
§Penile urethra- Deep inguinal nodes.