APK Chapter 25

primary vs accessory sex organs

primary:

• produce sex cells (gametes)

• male: testes

• female: ovaries

accessory:

• all other aspects of reproductive anatomy

• nourish and transport the gametes

• include external genitalia

primary and accessory sex organs of males

primary:

• testes

accessory:

• epididymis

• ductus deferens

• ejaculatory duct

• urethra

• seminal vesicles

• prostate gland

• penis

• scrotum

• bulbourethral gland

travel route of sperm

seminiferous tubules

straight tubules

rete testis

efferent ductules

epididymis

ductus deferens

ejaculatory duct

prostatic urethra

membranous urethra

spongy urethra

external urethral orifice

scrotum on thermoregulation

• cremaster muscle:

  • contracts to elevate testes toward the body when its cold

  • relaxes to lower testes away from the body when its warm

• dartos muscle:

  • contracts to wrinkle the scrotal skin, reducing SA and heat loss

  • relaxes to smooth the skin, increasing SA for heat dissipation

structures of the spermaticord

vessels (pampiniform plexus)

nerves

ductus deferens

accessory glands of male genitalia

seminal vesicles:

• paired glands located superior to urinary bladder

• source of 60% of seminal fluid

prostate gland:

• unpaired gland inferior to urinary bladder

• source of 30% of seminal fluid

bulbourethral glands:

• paired glands inferior to the prostate

• lubricates urethra and neutralizes acidic urine in urethra

structure of the penis

root (2 crura + bulb)

body (shaft)

glans penis: enlarged tip of shaft

prepuce: skin cuff at the distal penis

tissue of the penis

corpus spongiosum (unpaired/ventral):

• forms the glans penis distally

• forms the bulb of the penis proximally

• secured to urogenital diaphragm

corpora cavernosa (paired/dorsal):

• form the crura of the penis proximally

• secured to pubic arch

primary and accessory organs for females

primary:

• ovaries

accessory:

• fallopian tubes

• uterus

• cervix

• vagina

• mons pubis

• labia majora and minora

• clitoris

• external urethral orifice

• vaginal orifice

• greater and lesser vestibular glands

• paraurethral glands

components of the ovaries

• ovarian cortex

• ovarian medulla

• germinal epithelium

• tunica albuginea

• stroma

components of the fallopian tubes

• infundibulum

• ampulla

• isthmus

• interstitial segment

• ciliated simple columnar epithelium

• smooth muscle

• serosa

components of the uterus

• fundus

• body

• isthmus

• cervix

• endometrium

• myometrium

• perimetrium

components of the vagina

• vaginal canal

• vaginal fornix

• hymen

• stratified squamous epithelium

• rugae

• smooth muscle

• adventitia

components of the vulva

• mons pubis

• labia majora

• labia minora

• clitoris

• external urethral orifice

• vaginal orifice

• ducts of vestibular glands

• great vestibular glands

• paraurethral glands

structure of mons pubis (external female genitalia)

• a rounded fatty pad over the pubic symphysis containing adipose tissue

• cushions the pubic bone

structure of body of clitoris (internal female genitalia)

• the shaft of the clitoris made up of 2 corpora cavernosa

• lies posterior to the glans and extends backward under the pubic symphysis

• becomes engorged with blood during sexual arousal

pathway of ovum

• ovum develops into a follicle within the ovarian cortex

• a mature follicle ruptures releasing the ovum into the peritoneal cavity near the fimbriae

• the ovum goes to the infundibulim

• then it goes to the ampulla, where fertilization occurs

• it goes through the isthmus, pass the uterine wall, and into the uterine cavity

• if fertilization occurred the zygote travels to the uterus and implants itself in the endometrium of the uterine body

• if no fertilization occurs, the ovum degenerates, hormone levels drops, and the endometrium sheds

• the ovum exits the uterus via cervical canal → vagina → external vaginal orifice

penis vs. clitoris

penis:

• made of 2 corpora cavernosa + 1 corpus spongiosum

• has glans penis

• prepuce covers glans penis

• crura present

• bulb of penis

• functions in urination and sperm delivery

• urethra is inside

• produces semen

clit:

• made of 2 corpora cavernosa

• has glans clitoris

• prepuce covers clitoral hood

• crura present

• bulb of vestibule

• functions in sexual arousal

• urethra is separate

• no secretions

pampiniform plexus on thermoregulation

• a network of interconnected veins that surrounds the testicular artery with the spermatic cord

• countercurrent heat exchange system:

  • cool venous blood from the testis absorbs heat from the incoming warmer arterial blood

  • this cools the blood entering the testis and helps maintain an optimal temperature for sperm production

structure of labia majora (external female genitalia)

• thick longitudinal folds of skin extending from the mons pubis containing sebaceous/sweat glands, adipose tissue, and smooth muscle

• protects labia minora, clitoris, and vaginal/urethral orifices

structure of labia minora (external female genitalia)

• two thin, hairless folds medial to the labia majora

• highly vascularized and rich in sebaceous glands

• encloses the vestibbule and helps direct urine and secretions. protects opening of vagina and urethra

structure of clitoris (external female genitalia)

• small cylindrical structure located at the anterior junction of the labia minora

• glans glitoris, body, crura, prepuce

• made of erectile tissue and functions in sexual arousal and pleasure

structure of vestibule (external female genitalia)

• a recess containing the external urethral and vaginal orifices

• contains external urethral orifice and vaginal orifice

structure of crus of clitoris (internal female genitalia)

• paired, elongated structures made of sorpora cavernosa that run along the ischiopubic rami

• support and anchor the clitoris

structure of bulb of vestibule (internal female genitalia)

• paired, elongated massess of erectile tissue located on either side of the vaginal orifice

• contributes to tightening of vaginal orifice