urogenital one

Question 1

what is origin of urogenital system?

Answer 1

the intermediate mesoderm

Question 2

what part of primordia becomes male?

Answer 2

mesonephric

Question 3

what part of primordia becomes female?

Answer 3

paramesonephric

Question 4

what does intermediate mesoderm form on either side of the aorta?

Answer 4

urogenital ridge

Question 5

where is intermediate mesoderm?

Answer 5

between somites and lateral plate mesoderm

Question 6

how does urogenital ridge form?

Answer 6

with lateral folding of embryo, intermediate mesoderm bulges into the peritoneal cavity

Question 7

what two structures are formed in urogenital ridge?

Answer 7

nephrogenic cord (kidney) and gonadal ridge (genital)

Question 8

what three sequential kidneys does nephrogenic cord form from head to tail?

Answer 8

1. pronephros
2. mesonephros
3. metanephros

Question 9

what is mesonephric duct?

Answer 9

embryonic ureter

Question 10

what is metanephric diverticulum?

Answer 10

basis of our kidney

Question 11

role of pronephros

Answer 11

forekidney; rudimentary, nonfunctional, 4th week

Question 12

role of mesonephros

Answer 12

midkidney -(second month) temporary, functional, amphibians, ducts are conserved as male genital ducts and become efferent ductules of testes

Question 13

role of metanephros

Answer 13

hindkidney - permanent, developed at 5th week. will become permanent kidneys

Question 14

permanent kidneys develop from two source:

Answer 14

metanephric diverticulum or ureteric bud

metanephric mass of intermediate mesoderm

Question 15

ureteric bud

Answer 15

primordium of ureter, renal pelvis, calices, and collecting tubules in the pyramids (collecting system)

Question 16

metanephric mass of intermediate mesoderm

Answer 16

will differentiate into kidney nephrons.

Question 17

what becomes ureter

Answer 17

the stalk of utereric bud

Question 18

what will distal portion of ureteric bud do?

Answer 18

undego repetitive branching

Question 19

what is transcription factor WT1?

Answer 19

regulates synthesis of Glial-derivid neurotrophic factor (GDNF) which induces branching of ureteric bud

Question 20

how long do ureteric buds develop?

Answer 20

continue to bifurcate until 32nd week, producing 1 to 3 million collecting ducts

Question 21

until when are nephrons formed?

Answer 21

until birth. after birth they increase in size, not in number

Question 22

how does differentiation of nephrons start

Answer 22

with metanephric tissue cap, which differentiatews into metanephric vesicles, which form s-shaped metanephric tubules. proximal end of tubules is invaginated by small blood vessels. capillaries differentiate into glomerulus. metanephric vesicles and tubules become bownman’s capsule, proximal convoluted tubule, loop of Henle, distal convoluted tubule.

Question 23

kidney ascent

Answer 23

mesonephros degenerates as kidney ascends. due to embryo growth.

Question 24

what hooks up to kidneys as they ascend?

Answer 24

sequential arteries. some may persist. kidney becomes retroperineal.

Question 25

when do metanephric kidney and glomerular filtration begin to work?

Answer 25

at approx week 9.

Question 26

are fetal kidneys responsible for waste excretion?

Answer 26

no. placenta does this.

Question 27

urorectal septum

Answer 27

divides cloaca into rectum and urogenital sinus with bladder, pelvic and phallic parts

Question 28

origing of bladder and urethra

Answer 28

endodermal cloaca

Question 29

how is cloaca partitioned?

Answer 29

dorsal portion: rectum and anal canal | ventral portion: bladder and urogenital sinus

Question 30

what does urogenital sinus give rise to?

Answer 30

bladder and lower urogenital tracts

Question 31

indifferent stage of sexual development

Answer 31

early genital development. gonads do not begin to attain sexual characteristics until week 7. external genitalia do not acquire distinct masculine or femininte char. until week 12

Question 32

primordial germ cells visible when and where

Answer 32

4 weeks in yolk sac

Question 33

primordial germ cells migrate into

Answer 33

along dorsal mesentery into gonadal ridges. if they do not migrate, gonads do NOT develop.

Question 34

indifferent gonads

Answer 34

indentical in both sexes before week seven. development begins with gonadal ridge. then will consist of cortex and medulla.

Question 35

germ cells migrate along dorsal mesentery and

Answer 35

by week six, induce differentiation of the gonad into testis or ovary

Question 36

paramesonephric ducts

Answer 36

form during week six lateral to mesonephric ducts

Question 37

what are primary sex cords?

Answer 37

fingerlike projections of epithelial cells that grow into mesenchyme of the gonadal ridge and form cortex and medulla

Question 38

what does cortex develop into?

Answer 38

ovary in embryos with XX chromosomes. medulla declines.

Question 39

what does medulla develop into?

Answer 39

testes in embryos with XY chromosomes. cortex regresses.

Question 40

testis development steps

Answer 40

a. paramesonephric duct degenerates b. primary sex cords become seminiferous cords, filled with sertoli cells. c. mesonephric duct becomes ductus deferens

Question 41

ovary development steps

Answer 41

a. mesonephric ducts degenerate b. secondary sex cords - cortical cords break up inhto primordial follicles c. no tunica albuginea two paramesonephric ducts fuse in midline to form uterus

Question 42

what tissue is involved in external genital development?

Answer 42

mesoderm and ectoderm around cloacal membrane

Question 43

primordial tissues of external genitalia from from

Answer 43

1. a pair of labrioscrotal folds 2. a pair of genital folds 3. an anterior genital tubercle

Question 44

genital tubercle

Answer 44

forms a primordial phallus

Question 45

genital folds

Answer 45

inner and outer extend dorsally from genital tubercle.

Question 46

urogenital folds

Answer 46

inner folds

Question 47

labioscrotal folds

Answer 47

develop on each side of urogenital folds. grow toward each other and fuse to form scrotum.

Question 48

differentiation of female genitalia

Answer 48

genital tubecle elongates and eventually becomes clitoris urogenital folds form labia minora labioscrotal folds become labial majora

Question 49

prepuce

Answer 49

foreskin

Question 50

origin of penile urethra

Answer 50

ventral fusion of the urogenital sinus

Question 51

original of navicular fossa in glas

Answer 51

ectodermal invagination from end of penis

Question 52

how does mesonephros change function?

Answer 52

from urinary to genital in the male

Question 53

what can improper interaction of epithelium and mesoderm lead to in the development of the metanephric kidney?

Answer 53

lack of glomerular development

Question 54

cause of ectopic kidneys

Answer 54

result of an incomplete or missing ascent (kidney is stuck in pelvis)

Question 55

what is hydronephrosis?

Answer 55

(enlarged renal pelvis) swelling of one kidney due to a backup of urine by the compressed ureter. artery blocks ureter. urine passage from kidney is blocked by renal artery. renal veins can also cause it. surgical treatment.

Question 56

crossed kidney/ crossed ectopia

Answer 56

kidney migrates to the other side so that both kidneys are on same side

Question 57

horseshoe kidney

Answer 57

two kidneys become fused in ascent. in more than 90% of cases, fusion occurs along lower pole. normally asumptomatic.

Question 58

duplex kidney

Answer 58

the development of an extra kidney or partially fused kidney on one side or the other. a kidney can also have two ureters.

Question 59

POLYCYSTIC KIDNEY DISEASE

Answer 59

ARPKD, autosomal recessive disease. multiple fluid filled cysts form in kidneys. 1:2000 births. lethal if not treat by transplantation. thought to be caused by abnormal cell proliferation in the tubule cells that leads to blockage of the tubules resulting in fluid build-up in segments of the tubules.

Question 60

how is PKD treated?

Answer 60

control high blood pressure surgery to reduce pain antibiotics to resolve infections

Question 61

female pseudohermaphroditism

Answer 61

(male external genitalia in female) intersexual condition: chromosomally and gonadally female with XX karyotype 1:10,000 births cause: mother exposed to excessive androgens congenital adrenal hyperplasia usually no ovarian abnorality, but excessive production of testosterone masculinizing materla tumors also cause this

Question 62

congeintal adrenal hyperplasia

Answer 62

autosomal recessive, decreased synthesis of cortisol due to an enzyme deficiency

Question 63

male pseudohermaphroditism

Answer 63

intersexual condition. XY, 1:10,000 ext. and int. genitalia are variable caused by variations in devt of external genitalia and paramesonephric ducts caused by inadequate production of testosterone or reduced tissue responsiveness in the fetus this can be caused by genetic defects in enzymatic production of testosterone by fetal testes and interstitial cells of testes

Question 64

androgen insensitivity syndrome (AIS)

Answer 64

``` 1:20,000 normal appearing female but XY masculinization of male genitalia in fetus is impaired external ge. are female uterus doesnt work amenorrhea testes in abdomen ``` results from fact that target male reproductive cells are resistant to testosterone (androgen receptor problem)