MALE UROGENITAL SYSTEM GROSS ANATOMY Flashcards
reproductive system definition
the biological system made up of all the anatomical organs involved in sexual reproduction
two external genital organs
penis and scrotum
explain gross structure of penis
penis- formed of root, containing the bulb of penis and crura, formed of corpora cavernosa
body- shaft
neck
glans penis- bulbous shaped top, supported and protected by the foreskin formed of corpus spongiosum
explain more complex penis structure
consists of three cylindrical masses of erectile tissue, two corpora cavernosa lying adjacent to each other
corpus spongiosum lying ventrally and surrounding the uretrha
where does the bulb of the penis lie?
superficial perineal pouch
what is the ventral side of the penis marked by?
a groove in the lateral direction
where is the foreskin attached?
underside of the penis by the frenulum
three different parts of the urethra explained
prostatic- when passing through the prostate
membranous- passes through the perineal membrane, forming the narrowest part of the male urethra
penile- when in the penis
scrotum definition
structure located caudal to the penis, consisting of a suspended dual chambered sack of skin and smooth muscle
it is a distention of the perineum
what does the scrotum contain
external spermatic fascia, testes, epididymus and ductus deferens
two important muscles in the scrotum
cremaster muscles and dartos muscles
location of cremaster muscles
muscle that covers the testis and spermatic cord
between the external and internal spermatic fascia
structure of cremaster muscle
paired structure
thin layer of skeletal striated muscle
function of cremaster muscle explained
raise and lower testes in order to regulate scrotal temperature for optimal spermatogenesis and survival of resultant spermatozoa
involuntary muscle, contraction can occur during arousal which can prevent injury to the testicles during sex
contract during ejaculation
important reflex explained
cremaster reflex
stroke skin from inner thigh towards knee
stimulates sensory fibres of ilioinguinal nerve
stimulates motor fibres of the genital branch of the geniofemoral nerve
provides innervation to cremastor muscles causing the contraction of the muscle and elevation of testes
how else can the cremaster be stimulated to contract?
performing Kegels or by flexing and tightening abdominal muscles
movement of pulling testes superiorly
retraction
dartos structure + location
dartos fascia is an external layer of connective tissue with muscle found in the penile shaft, foreskina nd scrotum
dartos function
carries blood supply of the penile skin
acts to regulated temperature of testis by expanding or contracting to wrinkle the scrotal skin
contraction reduces the SA available for heat loss- worming testicles
dartos muscle works in conjuction with cremaster
testis definition
primary sex organs of the male and produce spermatozoa and hormones
structures within testis
seminiferous tubules, epidyimus, rete testis, vasa efferentia, vas deferens
seminiferous tubule structures
several coiled tubules within the central testes, sites of spermatozoa production
explain drainage from seminiferous tubules
drain from the testes into the rete testis
then via a series of vasa efferentia tubules into a coiled single duct of the epididymus
epididymus then becomes the uncoiled ductus deferens at the posterior pole of the testis
ductus deferens enters the spermatic cord, passing through the inguinal canal, reching the urethra
what is the spermatic cord?
cord like structure formed by the vas deferens and surrounding tissue that runs from the deep inguinal ring down to each testicle