Anatomy 3: Pelvic Organs - General Viscera and Male Pelvic Organs Flashcards Preview

Block I: Reproduction & Sexuality > Anatomy 3: Pelvic Organs - General Viscera and Male Pelvic Organs > Flashcards

Flashcards in Anatomy 3: Pelvic Organs - General Viscera and Male Pelvic Organs Deck (35):

Describe the peritoneum's relationship with the rectum

  • Covers the anterir and lateral walls of the superior 1/3 of the rectum
  • Covers only the anteior surface of the middle 1/3
  • The inferior 1/3 is sub-peritoneal


Describe the muscle layers around the rectum

  • Outer longitudinal
  • Inner circular


Functio nof puborectalis muscle

Acts as a muscular sling that kinks the anorectal junction. Functions in the maintenance of fecal continence


Artery from which the superior rectal artery originates

Inferior mesenteric artery


Artery from which the middle rectal artery originates

Internal iliac artery


Artery from which the inferior rectal artery originates, and the artery from what that originates

Internal iliac artery --> internal pudendal artery --> inferior rectal artery


Where does the inferior mesenteric vein empty into?

Portal System


5 main vessels of the portal system

  • Portal vein
  • Superior mesenteric vein
  • Superior rectal vein
  • Inferior mesenteric vein
  • Splenic vein


Define the ureter

Retroperitoneal muscular ducts ~25-30 cm long


What crosses the ureters anteriorly

Gonadal vessels


What does the ureter cross to enter the pelvis

Bifurcation of the common iliac artery


3 places where the ureters are normally constricted

  • Junction of the ureters and the renal pelvis
  • Where the ureters cross the brim of the pelvic inlet
  • During their passage through the wall of the bladder


Label these 7 internal features of the bladder

See image


FUnction of parasympathetic fibers with respect to micturation

Contraction of the detrusor muscle and are inhibitory to the internal involuntary sphincter (allows voiding)


Function of sympathetic fibers with respect to micturation (3)

  • Induce relaxation of the bladder walla nd constrict the internal sphincter (inhibit emptying)
  • Prevents semen from entering the bladder in males during ejaculation
  • Make you unable to void from self-consciousness


Full bladder volume

300 mL or more


Describe how voiding occurs physiologically (6 steps)

  1. Bladder full and stretched
  2. Visceral afferent fibers are stimulated
  3. Impulses enter S2-4 via pelvic splanchnicnerve (parasympathetic)
  4. Efferent fibers transmit impulses back to the bladder
  5. Recontractio nof the detrusor muscle reflexively
  6. Internal sphincter relaxes

NOTE: Can suppress this reflex by voluntary control of the external urethral sphincter


Describe the trajectory of the vas deferens

  1. Continuation of the epididymis
  2. Passes through the inguinal canal within the spermatic cord to enter the abdomen
  3. Descends into the true pelvic along its lateral walls just deep to the peritoneum
  4. Crosses over the ureter and travels to the posterior surface of the bladder
  5. Enlarges posterior to the bladder into the ampulla of the vas


What forms the ejaculatory duct?

  • Duct of the ampulla
  • Duct of the seminal vesicle


Location of the seminal vesicles

  • Paired organs
  • Lie on the posterior surface of the bladder between the bladder and the rectum
  • Lateral to the terminal parts of the vas deferens


Where do the seminal vesicles empty into

Short duct at the inferior end that fuses with the duct of the ampulla of the vas


Where do the ejaculatory ducts open into?

The prostatic part of the urethra (prostatic urethra) near the orifice of the prostatic utricle


Define the prostatic utricle

The tiny vesitgial development homologue of the uterus


5 lobes of the prostate

  • Ventral/anterior lobe
  • Lateral lobes (2)
  • Posterior lobe
  • Middle lobe


Location of ventral/anterior lobe of prostate

Anterior to the urethra


Location of lateral lobes of the prostate

Lateral to the ejaculatory ducts


Location of the posterior lobe of the prostate

Between the ejaculatory ducts


Location of the middle lobe of the prostate

Above the ejaculatory ducts


5 functional zones of the prostate

  • Anterior fibromuscular zone
  • Preprostatic sphincter
  • Transitional zone
  • Central zone
  • Peripheral zone


Location of the central zone of the prostate

Posterior to the urethra and surrounds the two ejaculatory ducts


Location of the transitional zone of the prostate

Mainly anterior and superior to the prostatic colliculus


Location of the preprostatic sphincter

Surrounds the proximal prostatic urethra and is surrounded by the transitional zone


Location of the peripheral zone of the prostate

Extends over the posterior and lateral surfacees of the prostates


Location of the anterior fibromuscular zone

Anterior part of the prostate


Function of the prostate

Generate ~20% of the seminal fluid which enters the prostatic urethra through 20-30 ducts that open into the prostatic sinus