Answer
6A. Deep transverse perineal muscle;
Location: in deep perineal space
Action: anchors perineal body, and supports vaginal and urethral canals
Origin: ischiopubic rami
Insertion: perineal body
Innervation: pudendal nerve
6B. Compressor urethrae muscle -- found only in females
Location; deep perineal space
Action: aids in retention of urine
Origin: ischiopubic rami
Insertion: both meet inferior to external urethral sphincter
Innervation: pudendal nerve; spinal nerves S2-S4 plus pelvic splanchnic nerve
6C. External anal sphincter
Location: in anal triangle
Action: retains feces until voluntary voiding
Origin. coccyx and perineal body
Insertion: encircles anal canal and anal orifice
Innervation: pudendal nerve; spinal nerves S2-S4 and pelvic splanchnic nerve
Work Step by Step
The compressor urethrae muscle is the only muscle that is found in human females but not in males.
