LEC35: Reproductive Tract II Flashcards Preview

Structures: Part Deux > LEC35: Reproductive Tract II > Flashcards

Flashcards in LEC35: Reproductive Tract II Deck (64)
Loading flashcards...
0
Q

what partitions cloaca, and what does it partition it into?

A

urorectal septum

posterior region: rectum

anterior region: bladder

1
Q

when are genitalia undifferentiated

A

4-7 weeks

2
Q

what membranes form from cloacal partitioning?

A

urorectal septum

creates:

anterior: urogenital membrane
posterior: anal membrane

at 6 weeks!

3
Q

when and how does the urethral plate form?

A

development of male external genitalia

endodermal cells proliferate, fold upon itself > urethral plate

2 edges of plate meet, ectoderm fuse, closing urethra inside penis

4
Q

what forms spongy urethra area?

A

urogenital folds

5
Q

how does penile (median) raphe form?

A

surface ectoderm of urethral plate meet, fuse as line down ventral side of penis

6
Q

how does scrotal raphe get created?

A

labioscrotal swellings come together

7
Q

what is urethral epithelium made of?

A

both spongy urethra and ectoderm; surrounded by connective tissue

8
Q

which part of cloaca does spongy urethra come from?

A

distal part

9
Q

what is meant by the urethra’s dual origin?

A

canalizing betweeen spongy urethra (endoderm) and glandular part of spongy urethra (ectoderm) forms urethra urethral orifice at tip

10
Q

what does prepuce form from and when

A

at tip of foreskin middle ectoderm cells die, form cleft week 12

11
Q

what are the 2 penile rathes, where do they come from?

A

labio-scrotal fusion > scrotal rathe urethral folds fusion > penile rathe

12
Q

where do labio scrotal folds first fuse?

A

dorsally/posteriorly

13
Q

what forms labia minora

A

unfused urogenital folds

14
Q

what forms labia majora

A

unfused labioscrotal folds

15
Q

what produces estrogens > female genitalia development?

A

mostly placenta, some from fetal ovaries also

16
Q

where is clitoris nestled

A

between labio-scrotal swellings

17
Q

what is the hymen

A

tissue that hasn’t canalized with the outside; thin membrane of tissue remains; breaks either at first intercourse or spontaneously

18
Q

what are the parts of the labia majora that first form?

A

posterior fusion > posterior commissure anterior fusion > anterior commissure middle remains open > labia majora

19
Q

homologous structures of urogenital sinus

A

male: bladder, urethra (part), prostatic utricle, prostate, bulbourethral glands female: bladder, urethra, vagina, para/urethral glands, bartholins

20
Q

homologous structures from genital tubercle

A

male: penis female: clitoris

21
Q

homologous structures from urogenital folds

A

male: ventral penis female: labia minora

22
Q

homologous structures from labioscrotal folds

A

male: scrotum female: labia majora

23
Q

typical sexual differentiation def’n

A

external and internal genitalia consistent with sex chromosome content

24
Q

errors in sex determination and differentiation def’n

A

disorders of sexual development, incongruence between external genitalia, internal genitalia, sex chromosome content

25
Q

ovotestis

A

both ovarian and testicular tissue present, either in same or opposite gonads majority 46XX, others 46XX/46XY or 46XY ovotestis nonfunctional - no egg or sperm produced ambiguous genitalia- clitoral enlargement/penile underdevelopment indistinguishable at birth causes poor understood, very rare

26
Q

why might 46XX individual manifest/what do you see?

A

internal genitalia not different, external genitalia virilization due to exposure of female fetus to excess androgens

27
Q

CAH

A

congenital adrenal hyperplasia cause- overexposure to androgens occurs b/c steroid hormones from adrenal gland, cholesterol based hormones metabolized - 12 hydroxylase precursors shunted to produce excess testosterone even in female who’s missing 12 hydroxylase

28
Q

how to treat CAH in known carrier

A

give pt high doses of steroids that overcome block in pathway, prevent masculinization of female penis

29
Q

how does 46XY individual appear

A

male with feminized genitalia; opp of CAH variable external/internal genitalia due to inadequate testosterone, MIS production by fetal testes can have normal or very rudimentary testes 5 alpha reductase deficiency > many diff manifestations from this

30
Q

androgen insensitivity syndrome

A

aka testicular feminization - normal-appearing females 46XY normal hormone produce, but cell surface receptors don’t receive testosterone correctly - defect in androgen receptor female external genitalia; blind-ending vagina; absent/rudimentary uterus - vaginal plate doesn’t break down

31
Q

hypospadias incidence, cause

A

incidence: 1/300 inadequate production of androgens and/or inadequate receptors > failure of canalization of ectodermal cord and/or failure of fusion of urogenital folds > incomplete spongy urethra forms most commonly, distal end of urethra, under urethral orifice- see opening in glans of penis

32
Q

agenesis of external genitalia cause, presentation

A

very rare urethra opens into perineum near anus- no genital tubercle develops congenital absence of clitoris/penis

33
Q

different causes of anomalies of uterus and vagina

A

1) incomplete fusion of paramesonephric ducts 2) incomplete development of a paramesnophric duct 3) incomplete canalization of vaginal plate to form vagina

34
Q

uterus didelphys

A

incomplete fusion of distal/inferior part of paramesonephric duct

35
Q

bicornuate uterus

A

incomplete fusion of upper part of paramesonephric duct; duplication only of superior part of body of uterus

36
Q

bicornate uterus with rudimentary horn

A

unequal incomplete fusion- more rudimentary horn on 1 side than the other, 1 short and 1 long portion, pregnancy usu forms in longer portion hematocolpos - no communication between inside and outside

37
Q

hematocolpos

A

no communication between inside and outside in bicornate uterus w/ rudimentary horn when woman menstruates, blood from endometrium and sloughs off starts to accumulate inside uterine cavity b/c has nowhere to go blood collects behind cervix very painful

38
Q

septate uterus

A

abnormal fusion of septum - external uterus appears normal, internal septum present though one cause for recurrent miscarriages, but fixable very common!

39
Q

unicornuate uterus

A

results from failure of 1 paramesonephric duct to develop, have only 1 half of uterus

40
Q

why would vaginal atresia occur? common?

A

absence of vagina/uterus very rare - 1/80,000 failure of endoderm and ectoderm to fuse, failure of sinovaginal bulbs to develop and form vaginal plate, so get no canalization of vaginal plate, blockage of vagina

41
Q

what do inguinal canals provide

A

pathway for descent of testes through anterior abdominal wall, into scrotum

42
Q

gubernaculum

A

long connective tissue strand connecting gonad-labioscrotal swellings of scrotum pulls testes down into scrotum, through inguinal canal

43
Q

what does inguinal canal form from

A

evagination of peritoneum ventral to gubernaculum

44
Q

what forms coverings of spermatic cord/testes

A

layers of tissue from abdominal wall that get pulled down as testes descent into scrotum via gubernaculum pulling

45
Q

what does gubernaculum become

A

tiny strand of tissue, anchoring down scrotum remains to scrotal sac

46
Q

where do 2 inguinal canal rings form from

A

deep inguinal ring: external oblique m. superficial inguinal ring: transversalis fascia

47
Q

what enables testes to pass through deep inguinal rings?

A

atrophy of paramesonephric ducts

48
Q

what guides testes through inguinal canal?

A

processus vaginalis

49
Q

what happens as testes descent?

A

enlarge, mesonephric kidneys atrophy, paramesonephric ducts atrophy, processus vaginalis guides thru canal

50
Q

what helps testes descned through canal

A

increase in intra-abdominal pressure from enlarging abdominal organs

51
Q

when do testes descend

A

26 weeks

52
Q

where do testes move from/to

A

“relative movement” from posterior abdominal > inguinal canal > scrotum

53
Q

do all newborns have descended testes?

A

no, 97% spontaneous descent no longer occurs after 1 yr

54
Q

what does transversalis fascia become in testes coverings?

A

internal spermatic fascia

55
Q

what does internal oblique m. become in testes coverings?

A

cremasteric m./fascia

56
Q

what does external oblique m. become in testes coverings?

A

external spermatic fascia

57
Q

what happens to processus vaginalis after testes descent

A

during perinatal pd, remnant of stalk of processus vaginalis obliterates tunica vaginalis remains as isolated peritoneal sac around testes

58
Q

cryptorchidism

A

undescended testes anywhere along pathway of descent caused by androgen deficiency in fetal testes if remain undescended, increased risk of sterility, testicular cancer

59
Q

ectopic testes cause

A

gubernaculum passing to abnormal location

60
Q

congenital inguinal hernia

A

failure of complete closure btwn tunica vaginalis & peritoneal cavity persistent processus vaginalis remains

61
Q

what does gubernaculum become in females

A

ovarian ligament, connects ovary-uterus, and round ligament

62
Q

where does gubernaculum pull down into in female

A

labium majora, to labial-scrotal swellings

63
Q

hydrocele

A

abdominal end of processus vaginalis has small opening, allows peritoneal fluid to pass through