The Urogenital System - The Reproductive Organs

ANSC 309

list the male reproductive organs

• gonads (paired)

• gonadal duct system (paired)

• accessory glands

• urethra

• penis

what are the singular and plural forms of gonads?

singular — testis, testicle

plural — testes, testicles

function of gonadal duct system?

convey the sperm and seminal fluid of the testes to the urethra

two structures within the gonadal duct system?

• epididymis 

• ductus deferens

what male reproductive organ contributes to the bulk of semen?

accessory glands

name the accessory glands

• prostate gland

• vesicular glands

• ampullary glands

• blubourethral glands

placement of urethra…

extends from the bladder to the free extremity of the penis

function of urethra?

serves for the passage of both urine and semen

function of penis?

deposits the semen within the reproductive tract of the female

what are the skin structures associated with the penis and testicles?

• prepuce

• scrotum

the testis ranges in ______, ______ and ________ depending on species

size, shape, and orientation

shape of testis in cats and swine

tilted toward the anus

shape of testis in horses and dogs

horizontally oriented between the hindlimbs

shape of testis in ruminants

vertically oriented and pendulous between thighs

describe the testis

solid encapsulated ellipsoidal organ outside of the body cavity which is suspended within the scrotum by a spermatic cord

what does the testis produce?

• testosterone

• sperm, spermatozoa

what is the tough, outer layer of connective tissue that surrounds the testis?

Tunica Albuginea

the soft, yellowish or brownish testicular parenchyma consists of ________ _________

seminiferous tubules 

where does spermatogenesis occur?

in seminiferous tubules

what are the 2 cell types that line seminiferous tubules?

• Sertoli cells

  • support and nourish sperm cells

• spermatogenic cells

  • produce sperm cells

the seminiferous tubules are surrounded by interstitial cells known as…

Cells of Leydig

function of Cells of Leydig?

secrete Testosterone

where do seminiferous tubules gather at?

the mediastinum of the testicle

the seminiferous tubules gather at the mediastinum and pierce the capsule to join the …

head of the epididymis

the epididymis is attached to the testicle from end to end and is responsible for…

for storing sperm cells

describe the epididymis

a firm organ attached to the testicle that is for numerous convolutions duct

the epididymis is divided into three parts. what are they?

head, body, tail

the tail of the epididymis continues to become the …

Ductus Deferens

the ductus deferens runs ______ to the epididymis

medial

the ductus deferens heads toward the testicular vessels that form…

the bulkier components of the spermatic cord

the constituents of the spermatic cord remain together as they pass through the _______ ________ but disperse at the _______ ______

inguinal canal; vaginal ring

the ductus deferens penetrates the ________ before finally entering the urethra

prostate

the testicle and spermatic cord are enclosed within a pocket of Peritoneum from the abdomen through the Inguinal Canal called the ________ _______

vaginal tunic

what is spermatic fascia and what does it surround?

it’s a continuation of abdominal and transversalis fascia, and surrounds the structures emerging from the superficial inguinal ring (this includes the vaginal tunic (spermatic cord) and cremaster muscle)

what are the 2 parts of the vaginal tunic?

• parietal vaginal tunic

• visceral vaginal tunic

parietal vaginal tunic

the outer layer of this diverticulum in the male and extends to the bottom of the scrotum

visceral vaginal tunic

closely fused to the testis and epididymis and surrounds the ductus deferens

what are the 2 parts of the spermatic cord?

• ductus deferens

• testicular artery and vein

the bulk of the spermatic cord consists of…

testicular arteries and veins

the testicular artery branches from…

the abdominal aorta

the testicular veins constitute the close-meshed ___________ ________

Pampiniform Plexus

what’s involved in the Pampiniform Plexus?

contortions of the testicular artery are involved

where does the pampiniform plexus branch from?

the caudal vena cava

function of accessory sex glands?

produce seminal plasma which nourishes, transports and activates sperm

seminal plasma

liquid noncellular portion of semen

ampullary gland

widening or enlargement of the wall of the distal portion of the ductus deferens

what animals have ampullary glands?

ruminants, horses and dogs

absent in cats and poorly developed in boars

vesicular glands

paired glands that are dorsocranial to the pelvic urethra and empty directly into the urethra

what animals have vesicular glands

some form in horses, ruminants, swine

absent in dog and cat

the vesicular glands are often referred to as what in horses? why?

referred to as seminal vesicles because they are sac-like with a lumen

prostate gland

lies near the junction between the bladder and pelvic urethra

great species variation regarding shape and location

bulbourethral glands

paired glands on either side of the pelvic urethra near the ischial arch

usually small and ovoid and are characterized by being quite dense due to the high degree of fibrous connective tissue within them

location of the penis

suspended below the trunk and is partly contained between the thighs, where it is anchored to the floor of the pelvis by a suspensory ligament in the large species

describe the penis in a quiescent (dormant) state

the free extremity is concealed within an invagination of the abdominal skin (the Prepuce) which opens at a variable site behind the umbilicus

describe the scrotum

a pouch divided by an external raphe and an internal median septum into 2 cavities, each of which is occupied by a testis, an epididymis, and the distal part of the spermatic cord

the lower part of the scrotum is molded on the testes and adjusts as…

as their position varies with the ambient temperature

the scrotal skin adheres to a tough fibromuscular layer called the…

Tunica Dartos

the Tunica Dartos also extends as a…

septum between the compartments that separately lodge the testes

the cremaster muscle adheres to the…

spermatic cord

what 2 structures aid in the cooling and warming the testicles depending on ambient temperature?

Tunica Dartos and Cremaster Mucle

what is a traditional castration (neuter) procedure?

removal of the testicles

what are alternative castration procedures to removing the testicle?

vasectomy — ligation of ductus deferens

what are common surgical complications in castrations?

• internal/external bleeding — testicular artery/vein

• dehiscence of surgery site

• scrotal swelling

list the female reproductive organs

• gonads (paired)

• oviducts (paired)

• uterus

• vagina

• vestibule

function of oviducts

capture the ova on their release from the ovaries and convey them to the uterus

function of uterus

where the fertilized ova are retained and nourished until prenatal development is complete

function of vagina

serves as both copulatory organ and birth canal

function of vestibule

continues the vagina to open externally at the vulva and doubles as a urinary passage

what do the ovaries produce?

ova and hormones (estrogen)

describe the ovaries

solid, ellipsoidal body, although it’s commonly made irregular by the projection from the surface of large follicles and corpora lutea

each ovary is suspended within the…

cranial part of the broad ligament

the parenchymatous zone (cortex) is bounded by a tunica and is strewn with _______ in various stages of development and regression

follicles

as follicles fill with more fluid in the ovary, what hormone increases in the body?

estrogen

each follicle in the ovaries contain a single ______

ovum

what is ovulation?

the follicle selected for maturity will rapidly fill with fluid until it ruptures

the cavity within the ruptured follicle will initially fill with a blood clot and then transition into what?

a solid body known as the Corpus Luteum

corpus luteal cells are the source of __________

progesterone

when corpus lutea regress, they are replaced by what?

by connective tissue scars called corpora albicans (white bodies)

what is the oviduct?

the small convoluted ducts that transport ova and sperm (aka Fallopian Tubes or uterine tubes)

the oviduct consists of:

• infundibulum

• ampulla

• isthmus

infundibulum

the terminal end of the oviduct and consists of a funnel-shaped opening which forms a pocket that “captures” the newly ovulated oocyte

what does the infundibulum lead directly into?

ampulla

describe the ampulla

makes up a majority of the oviductal length and merges with the isthmus of the oviduct; it is also the site of fertilization between the ovulated oocyte and spermatozoa

describe the isthmus

smaller in diameter than the ampulla; it’s connected directly to the uterus

what is the point of juncture between the isthmus and uterus called?

uterotubal junction

describe the uterus

“the womb”, the enlarged part of the tract in which embryos arrive to establish a means of physiologic exchange with the mother’s bloodstream

what constitutes the basis for classification of mammalian uteri?

the degree to which the uterine horns are developed

what are the 3 anatomical types of uteri?

• duplex uterus

  • 2 cervical canals leading to 2 separate uterine horns

• bicornuate uterus

  • 2 uterine horns and uterine body

• simplex uterus

  • uterine body only

in all domestic mammals, the median part of the uterus has 2 segments. what are they?

cervix and lumen of the cervix

function of cervix

provides a sphincter controlling access to and from the vagina

function of the lumen of the cervix

(aka cervical canal) is constricted and often almost occluded by mucosal folds

how is the extent of the cervix easily discoverable on rectal palpation?

on the basis of its firmness in comparison with the adjacent parts

the horns (cornua) of the uterus vary greatly in length based on _________

species

describe the look of the uterine horns in different mammals.

round in ruminants

straight and divergent in mares and bitches

intestine-like loops in sows

what are the layers of the uterus’ wall?

• serosal (perimetrium)

• muscular (myometrium)

• mucosal layer (endometrium)

describe the vagina

a long thin-walled tube that occupies the middle of the pelvic cavity

the cranial part of the vagina is purely ____________ _________ that runs from the cervix to the urethral orfice

reproductive passage

the caudal part of the vagina is called the _________, and extends from the urethral orifice to the vulva

vestible

what are the 2 arteries that supply blood to the female repro tract?

• ovarian artery

• uterine artery

the ovarian artery supplies blood to what organs?

supplies the ovary and branches in varying patterns to the uterine tube and cranial part of the horn of the uterus