Reproductive Anatomy Flashcards
Inguinal region
Important surgically since it’s site of inguinal hernias
Area of weakness of AL wall due to passage of spermatic cord in males
Inguinal canal is approximately 4cm long running inferomedially (parallel/superior to inguinal ligament
Inguinal canal
Main occupant is spermatic cord (males) or round ligament (females)
Opening at each end
Deep (internal) inguinal ring
Superficial (external) inguinal ring
Inguinal hernia
Protrusion of small intestine through the superficial inguinal ring
Extremely painful and must be surgically repaired
Very rare in women
Inguinal canal borders
Anterior wall = aponeurosis of external oblique
Posterior wall = transversalis fascia and reinforced by conjoint tendon
Roof = arching fibres of internal oblique
Floor = inguinal ligament
Sperm development
Sperm begins development in testis (seminiferous tubules ~800ft)
Partially mature sperm cells move into epididymus (~6m long)
Epididymus secretes a fluid that helps the sperm cells to finish maturing
Once fully mature sperm cells enter ductus (vas) deferens (muscular tube that conveys sperm from epididymus to ejaculatory duct, sperm are stored before each ejaculation)
Vasectomy
Severing of vas deferens near epididymus
Ductus deferens
Begins at tail of epididymus
Ascends in spermatic cord
Passes through inguinal canal
Crosses over external iliac vessels and enters pelvis
Passes along lateral wall of pelvis
Joins with seminal vesicle duct to form ejaculatory duct
Ejaculatory duct
End of ductus deferens joins with seminal vesicles (between bladder and rectum) to form ejaculatory duct
2 glands unite to form a single ejaculatory duct along with both ductus deferens (secrete alkaline fluid which mixes with sperm to counteract the acidic environment of vagina, provides majority of of fluid to make up semen (60% volume), fluid is rich in sugar (fructose) as a nutrient for the sperm)
Ejaculatory duct flows into urethra
Prostate gland
Largest accessory gland of male reproductive system (70% glandular tissue and 30% fibromuscular tissue)
Dense fibrous capsule
Muscular anterior surface to eject prostatic fluid
Prostatic fluid (~30% volume) is for lubrication of the urethra, protection, nourishment, and mobility of sperm
Bulbourethral gland
2 pea-sized glands posterolateral to urethra
Also called Cowper’s glands
Produce alkaline fluid to neutralize the acidic environment and lubricate vagina
Penis
Common outlet for urine and semen
Consists of a root, body, and glands penis
External urethral orifice is at distal aspect
Skin of penis covers the glans penis (prepuce or foreskin)
3 cylindrical bodies of erectile tissue
Corpora cavernosa and corpus spongiosum
Corpora cavernosa = primary erectile tissue, parasympathetic stimulation causes increase in blood flow via deep arteries, poor venous return when enlarged with blood
Corpus spongiosum = encases urethra
Sperm
Spermatogenesis takes about 64-74 days to full maturation
After ejaculation the sperm can live for about 48 hours in the female reproductive tract
~400 million sperm
0.001% survival to oviducts
Urination
Also called micturition
In males urethra is common pathway for ejaculate and urine
Vagina
Musculomembranous tube
Extending from the cervix of the uterus to the vestibule of the vagina (vaginal orifice)
Serves as excretory duct for menstrual fluid (rich blood and nervous innervation)
Forms inferior part of birth canal
Vaginal orgasm via g spot (grafenberg spot = small collection of nerves on ventral side of vagina)
Uterus
Thick walled
Pear shaped
Hollow muscular organ
Body lies superior to urinary bladder
Cervix portion lies between bladder and rectum and superior to vagina
Position of uterus changes with degree fullness of bladder and rectum
Enlarges significantly to accommodate fetus
Uterine tubes
Also called Fallopian tubes
Embryonically similar to ductus deferens (extend laterally from uterine body to ovaries)
Approximately 10cm long
Ovaries
Almond shaped glands located close to lateral pelvic wall
Rich blood supply via gonad (ovarian) artery
Embryonically similar to male
Female is born with ~700,000 eggs
Clitoris
Highly innervation and function solely as an organ of sexual arousal
Erectile organ located where labia minora meet anteriorly
Consists of a root and body (2 corps cavernosa, glans clitoris, prepuce (labia minora))
Vestibule
Space between labia minora
Contains external urethra orifice (2-3cm posteriorinferior to glans of clitoris) and vaginal orifice
Bulb of vestibule are paired masses of elongated erectile tissue on either side of vaginal orifice (embryonically similar to bulb (root) of penis and corpus spongiosum
Greater vestibular glands
On either side of vestibule and partly overlapped by bulbs of vestibule
Secrete lubrication fluid directly into vestibule in preparation for penis
Embryonically similar to Cowper’s glands
Breasts
Present in both males and females
Females have better developed mammary glandular tissue and increased fat deposits (modified sweat glands that enlarge during menstrual cycle due to FSH and LH)
Lie superficial to pectoralis major and serratus anterior
Firmly attached to dermis of overlaying skin via suspensory ligaments which are invested with adipose tissue
Embryologic similarities
Male - female Testes - ovaries Scrotum - labia majora Penis - clitoris Ductus deferens - uterine tube Spermatic cord - round ligament Prepuce - labia minora Bulb (root of penis)/corpus spongiosum - bulb of vestibule Bulbourethral (Cowper’s) glands - greater vestibular glands
