conception Flashcards
4 step sexual response cycle
applies to both sexes
excitement
plateau
orgasm
resolution
excitement
Heightened sexual awareness/arousal and blood flow to erectile tissues (erection of the penis in males; erection of clitoris in females); vaginal and Bartholin’s gland secretions lubricate the female; male scrotum tightens and male secretes a lubricating fluid (bulbourethral glands)
plateau
Intensification of excitement phase responses, plus body responses (increased heart rate, respiratory rate, BP, muscle tension)
orgasmic
Male ejaculates semen; feeling of intense pleasure for sexual partners (orgasm); females may under multiple orgasms in
succession
resolution
Genitalia and body systems return to pre-arousal state; general feeling of relaxation; refractory period for males to repeat the cycle (varying length)
what mediates erection and ejaculation
spinal reflexes
hardening of the normally flacid penis to permit its entry to the vagina
erection
emptying the spem and excessory sex gland secreitons (semen) into the urethra
ejaculation- emmision phase
forceful expulsion of semen from the penis
ejaculation- expulsion phase
how is erection accomplished
engorgement fo the penis erectile tissue with blood as a result of marked parasympatheticaly induced vasodialation of the penile arterioles and mechanical compression of the veins
how is the emmision phase accomplished
sympathetically induced contraciton of the smooth muscle in the walls of the ducts and accesory sex glands
how is the expulsion phase accomplished
motor neuron induced contraction of the skeletal muscles are the base of the penis
where si the erection generating centre
lower spinal chord
how is the erection generating centre triggered
mechanically by touch sensitive glans penis; higher brain centres facilitate or inhibit this spinal reflex
spinal reflexive dialation of the penile arterioles
non adrenogenic neurons release NO to relax the arterioles and blood enters the erectile tisssues
engorgement
vacocongestion
how quickly is erection achieved
5-10 seconds
erection reflex summary
Lower spinal cord is the site of the
erection generating center;
mechanically triggered by the touchsensitive glans penis; higher brain
centers facilitate or inhibit this spinal
reflex
Spinal reflexive dilation of the penile
arterioles; non-adrenergic neurons
release nitric oxide (NO) to relax the
arterioles and blood enters the
erectile tissues
Draining veins are compressed by
engorgement (vasocongestion),
creating a closed system