Difference between revisions of "Erection - Anatomy & Physiology"

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* Stallion
 
* Stallion
* Increases in diameter during erection and [[Reproductive_Behaviour_-_Pre-copulatory_Behaviour_-_Anatomy_%26_Physiology#Penile_Protrusion|protrusion]].
+
* Increases in diameter during erection.
 +
* '''Retractor penis muscle''' still relaxes during erection, but '''no sigmoid flexure'''.
 +
* Engorgement with blood plays a significant role in the highly vascular penis.

Revision as of 10:00, 10 July 2008

Introduction

  • When sexual receptivity of the female is established and sufficient arousal is accomplished in the male, erection and protrusion of the penis ensue.
  • Successful penile erection requires a complex series of neural and vasomotor reactions.
  • Erection of the penis is necessary for copulation and deposition of semen in the female reproductive tract.
  • Erection is characterized by a marked increase in rigidity of the penis.
  • Increased rigidity is the result of increase in arterial inflow of blood compared to venous outflow.
  • Erection requires that blood be trapped within the cavernous sinus of the penis.
  • Increased blood flow to the penis is brought about by vasodilation of the arterioles supplying it.

Erection of the Fibroelastic Penis

  • Bull,Ram and Boar
  • Involves increased blood flow with subsequent increase in pressure and simultaneous relaxation of the retractor penis muscles.
  • Erection and protrusion involve straightening of the penis to eliminate the sigmoid flexure.
  • Does not increase significantly in diameter during erection.

Erection of the Musculovascular Penis

  • Stallion
  • Increases in diameter during erection.
  • Retractor penis muscle still relaxes during erection, but no sigmoid flexure.
  • Engorgement with blood plays a significant role in the highly vascular penis.