Week 1 Flashcards
What do the ovaries produce?
Oocytes and hormones (oestrogen, progesterone)
Why is the surface of ovaries scarred?
Wound healing process of menstruation
What arteries supplies the ovaries and where does it originate?
Ovarian arteries
Arises from the aorta at the level of the renal artery
What veins drains the ovaries and where do they empty?
Ovarian veins
Right - IVC
Left - renal vein
What is the lymphatic drainage of the ovaries?
Aortic nodes
What are the 3 main ligaments of the ovaries?
Broad - peritoneal sheet draped over uterus and tubes
Ovarian - fibrous cord, links ovary to uterus
Suspensory - links lateral wall of pelvis to ovary, carries ovarian artery and vein
Which ligament of the ovary carries the ovarian artery and vein?
Suspensory ligament
What are the rectouterine and uterovesical pouches and what is their importance?
Rectouterine - between uterus and rectum; deep
Uterovesical - between uterus and bladder; shallow
Peritoneal infection will spread to these areas which are very difficult to treat
Associated with endometriosis
What is the infundibulum of the uterine tube?
Funnel-shaped opening to peritoneal cavity, fringed by fimbriae
What is the ampulla of the uterine tube?
Middle section where fertilisation occurs, intricate folds in mucosa
What are the approximate measurements of the uterus?
7-8cm long, 5cm wide, 2.5cm thick
Highly variable
What is the internal os of the uterus?
Opening between the body of the uterus and the cervical canal
What is the external os of the uterus?
Opening between the cervical canal and vagina; different appearance post-childbirth (bounded by lips, more slit-like)
What is the fundus of the uterus?
Rounded superior portion, extends above the level of the uterine tubes
What is the isthmus of the uterus?
Narrowing between the body and canal
Which rare condition is caused by a malformation resulting in formation of 2 uterine bodies?
Bicornuate uterus
What is the normal anatomical position of the uterus?
Anteflexed - uterus body is bent forwards on the cervix
Anteversed - whole uterus is bent forwards at a right angle to the vagina
What is the blood supply and lymphatic drainage of the uterus?
Arterial - uterine artery (branch of internal iliac artery)
Venous - uterine vein (drains to internal iliac vein)
Lymphatics - body drains to para-aortic nodes, cervix drains to internal iliac nodes
What is the prostatic utricle?
Small dead-end channel found in the male prostatic urethra
Remnant of female vagina
What is the epididymis of the male reproductive tract?
Coiled structure
Part of the duct system allowing sperm to travel out of the body via the urethra
What is the vas deferens of the male reproductive tract?
Starts in the testes, loops over the bladder and enters the prostate
Carries sperm and semen for ejaculation
What is the bulbourethral gland of the male reproductive tract?
Mucus secreting gland
Small, located below prostate
What is retrograde ejaculation?
Backflow of semen to bladder where sperm are damaged by the acidic environment; negative consequences for fertility
What are the layers of the wall of the scrotum?
Skin Dartos fascia and muscle External spermatic fascia Cremasteric muscle and fascia Internal spermatic fascia
What is the function of the cremaster muscle?
Contracts/relaxes to raise/lower testis in cold/warm temperatures
What is the cremasteric reflex?
Stroking the upper inner thigh will cause the testes to rise on the same side
What is the tunica vaginalis of the testes and what is its clinical importance?
Closed sac of peritoneum with visceral and parietal layers between which exists a film of peritoneal fluid
Excess fluid forms a hydrocele
Outline the pathway of the duct system within the testes
Seminiferous tubules → straight tubule → rete testes → efferent ductules → epididymis → vas deferens
What is the blood supply and lymphatic drainage of the testes/scrotum?
Arterial - testicular artery
Venous - pampiniform plexus (to testicular vein and then IVC on right/renal vein on left)
Lymphatics - testis to para-aortic nodes, scrotum to inguinal nodes
What epithelium lines the epididymis and how is this adapted to its function?
Pseudostratified columar epithelium with stereocilia
Stereocilia increase surface area for fluid absorption so that composition can be monitored and adjusted
What type of contraction occurs in the vas deferens?
Peristalsis
What is the enlargement at the end of the vas deferens called and what outpouching lies here?
Ampulla
Seminal vesicle adds secretions
What is the function of the seminal vesicles?
Secretes an alkaline viscous fluid which helps to neutralise the acid in the female tract to protect sperm
What does seminal fluid contain?
Alkaline fluid, fructose (used for sperm ATP production), prostaglandins (sperm motility/viability and female contraction)
How is the ejaculatory duct formed and where does it extend to?
Seminal vesicle duct joins with the vas deferens
Penetrates prostate and empties into the urethra
What does the prostate gland do?
Secretes a slightly acidic fluid containing citrate (used by sperm for ATP production), acid phosphatase and proteolytic enzymes which liquefy coagulated semen
Which embryonic layer is the urogenital tract derived from?
Intermediate mesoderm
How many kidney structures form during embryonic development and what are they called?
3 Pronephros (cervical), mesonephros (abdominal), metanephros (pelvic)
In what week does the pronephros start to form?
Week 4
What is the pronephros?
Mesoderm solidifies into 7-10 cell clusters in the cervical region which are rudimentary and non-functional and regress
What is the mesonephros?
Upper thoracic and lumbar formation of unsegmented tubule shapes which drain into ducts and are technically functional
Contributes supporting cells to the genital ridge
Mesonephric duct forms and remains when mesonephros regresses
When is the metanephros formed and functional?
Appears in week 5
Functional by week 11
In what 2 parts is the metanephros formed?
Ureteric bud (outgrowth of mesonephric duct) Metanephric cap (circular mesenchymal structure around bud)
What is the cloaca?
Posterior orifice acting as a drain for urinary, reproductive and digestive tracts
Describe the role of the urorectal septum in embryological development
Urorectal septum divides the cloaca by fusion with the cloacal membrane to form the anterior urogenital sinus (bladder) and posterior rectal/anal canal
What forms the bladder in embryological development?
Urogenital sinus and caudal mesonephric duct (trigone)
What embryonic layer lines the bladder?
Endoderm
When are male/female morphological characteristics acquired in the embryo?
Week 7
What reproductive apparatus is present at the indifferent stage?
1 pair of gonads
2 pairs of genital ducts - lateral paramesonephric/Mullerian ducts (female) and mesonephric/Wolffian ducts (male)
What do the mesonephric ducts become in the male?
Form vas deferens and ejaculatory duct under the influence of testosterone
What do the paramesonephric ducts become in the female?
Form uterine tubes, uterus and superior vagina
Why do the paramesonephric ducts degenerate in the male?
Due to the action of anti-Mullerian hormone secreted by Sertoli cells
Why do the mesonephric ducts degenerate in the female?
Lack of stimulation from testosterone
In which week do the indifferent gonads appear?
Week 5
Where do primordial germ cells originate from and what do they form?
Yolk sac
Primitive sex cords
How are the primitive gonads formed?
Subset of epiblast cells move into the yolk sac for room to develop and then move back to urogenital ridge via dorsal mesentery to form the primitive gonads
Outline the development of the male gonads
Y chromosome encodes SRY testis determining factor → sex cords become horse-shoe shaped and break up into tubules → Leydig cells produce testosterone and Sertoli cells produce anti-Mullerian hormone → tunica albuginea forms and separates cords from surface epithelium → rete testes and mesonephric ducts fuse to form vas deferens
What characteristic of the testis cords changes in puberty?
Solid until a lumen is formed in puberty, giving rise to seminiferous tubules
Outline the development of the female gonads
Wnt 4 ovary determining gene
Primordial germ cells divide by mitosis → pool of oogonia - enter meiotic arrest at beginning of 4th month of gestation, now oocytes which become associated with follicular cells (primordial follicles)
In what week do the primordial germ cells migrate to the urogenital ridge from the yolk sac?
Week 6
In which week do the external genitalia begin to develop?
Week 3
Outline the development of the external genitalia
Pair of cloacal folds develop around cloacal membrane and join to form the genital tubercle → cloacal folds are subdivided into urethral folds and anal folds → genital swellings appear on each side of the urethral folds
How does the urethra develop?
Genital tubercle elongates into phallus → phallus pulls urethral folds forward → urethral folds form lateral walls of urethral groove and close over urethral plate to form the penile urethra
How does the lower vagina develop?
Sinovaginal bulbs grow out from urogenital sinus → bulbs fuse to form vaginal plate → hollows to form a cavity
What do the urogenital folds become in the male and female?
Male - ventral aspect of the penis
Female - labia minora
What do the genital swellings become in the male and female?
Male - scrotum
Female - labia majora
What does the gubernaculum become in the female?
Ovarian/round ligament
What is vaginal atresia?
Failure of the vagina to become hollow, no lumen development
What causes hypospadias?
Failure of urethral folds to fuse, causing holes to develop at any point along the penis
What is Kleinfelter’s syndrome?
47XXY
Leydig cells do not produce enough testosterone causing low sperm production, internalised testes and female appearance
What is testicular feminising syndrome?
46XY
Genetic male, external female
Testosterone is produced but X chromosome mutation causes a deficiency in receptors
What is Turner’s syndrome?
X0
Primordial germ cells degenerate at the urogenital ridge, causing failure in gonadal development and infantile genitalia
Where are peritubular myoid cells found?
Outside the basement membrane at the outer edge of seminiferous tubules in the testes
Which cells are responsible for the blood-testis barrier?
Sertoli cells
What does the blood-testis barrier do?
Prevents autoimmune destruction of developing gametes