Embryology-09-Urinary System Dev.

Front 1

kidney forms from

Back 1

intermediate mesoderm

Front 2

what does cloaca contribute to?

Back 2

bladder and urethra

Front 3

kidney development: 3 stage, with which structure

Back 3

nephrogenic cords of intermediate mesoderm

Front 4

where do nephrogenic cords form

Back 4

from cervical – sacral segments

Front 5

1st stage kidney development begins when

Back 5

3rd week

Front 6

stage name, & what develops

Back 6

proenephric phase – proenephric vessicles near cervical segments – vessicles link, form proenephric duct

Front 7

duct grows where?

Back 7

reaches and opens into cloaca

Front 8

during 4th week, what happens to duct?

Back 8

proenephros and cervical proenephric duct degenerate

Front 9

second phase of kidney development

Back 9

mesonephric – remaining proenephric duct now called mesonephric, is opposite thoracic/lumbar segment

Front 10

what develops in second stage

Back 10

mesonephric tubules, which open into mesonephric duct

Front 11

what do remnants of the second stage contribute to

Back 11

male reproductive system

Front 12

name of third development stage of kidneys

Back 12

metanephos

Front 13

where and when does third stage develop

Back 13

beginning in 5th week, at caudal mesonephric duct

Front 14

first sign of third stage

Back 14

ureteric bud appears

Front 15

ureteric bud forms what?

Back 15

grows into sacral portion of nephrogenic cord, and is called metanephric mass of mesoderm

Front 16

metanephric mass does what?

Back 16

tells ureteric bud to branch

Front 17

what two structures form the kidneys

Back 17

ureteric bud and metanephric mass

Front 18

ureteric bud does what

Back 18

collects urine

Front 19

ureteric bud becomes

Back 19

ureter, renal pelvis, calyces, collecting ducts/tubules

Front 20

metenephric mass becomes what

Back 20

glomerulus, nephrons (creating urine)

Front 21

metanephric mass forms what around ureteric bud

Back 21

metanephric mass forms condensation of masses of mesoderm cells around branches of the ureteric bud, called a TISSUE CAP

Front 22

tissue cap forms what

Back 22

metanephric vessicles: twist and elongate

Front 23

twisting, elongation of tissue cap forms

Back 23

loop of henle, convoluted tubules

Front 24

after twisting, what invades metanephric vessicle, where?

Back 24

blood vessel – invades blind end of metenephric vessicle – creates BOWMAN’s CAPSULE

Front 25

following vessel invasion, what occurs

Back 25

tissue breakdown between metenephric vessicle & ureteric buds – urine formed can drain through ureter

Front 26

derived from ureteric bud?

Back 26

urine collection system: ureters, pelvis, maj/min calyces, collecting ducts

Front 27

derived from metanephric mass

Back 27

urine production system: nephrons, (corpuscles, prox/distal conv. tubules, loops of Henle)

Front 28

if metanephric mass doesn’t link up with collecting syst?

Back 28

will make urine, but nowhere for it to go: kidney cyst

Front 29

kidney filled with cysts called

Back 29

multi-cystic kidney

Front 30

if multi-cystic kidney –why? how often? treatment?

Back 30

failure of ureteric bud vessicles to meet with metanephric mass, or atretic (blocked) ureter. usually only one kidney, about 1/4000 deliveries, leave kidney alone: will involute and disappear: body will use other kidney

Front 31

recessive polycystic kidney disease

Back 31

autosomal recessive, effects both kidneys, massive kidneys, filled with vessicles:take up normal healthy tissue space. collecting tubules are widely dilated. Children usually die. treatment: dialysis or transplant.

Front 32

coordinated kidney development depends on reciprocal interaction of what?

Back 32

ureteric bud and metanephric mass – interdependent structures

Front 33

metenephric mass triggers outgrowth of? how?

Back 33

sends chemical signals to mesonephric duct to send out ureteric bud & undergo branching

Front 34

ureteric bud triggers?

Back 34

sends out survival signals to metanephric mesoderm mass so that kidney tubules and tissue cap survive, nephrons form (condensation of metanephric mass, and tubologenesis)

Front 35

if no interaction between metanephric mass and ureteric bud, what occurs

Back 35

tissues will degenerate

Front 36

nephrons form but don’t join ureteric bud branches – result?

Back 36

nephrons can’t drain, may form cysts

Front 37

why do kidneys ascend

Back 37

probably differential growth – not well understood

Front 38

metanephric kidney appears where first?

Back 38

opposite sacral segments

Front 39

initially, what direction do kidney pelves face?

Back 39

anteriorly

Front 40

for kidneys to ascend, what occurs

Back 40

medial rotation, so hilus faces medially, differential growth causes ascent

Front 41

during ascent, what happens with blood supply

Back 41

old vessels degenerate, new vessels serve kidneys

Front 42

vessels that don’t degenerate during kidney ascent are?

Back 42

accessory renal vessels

Front 43

ectopic kidney can be

Back 43

anywhere along line of ascent that is not ‘correct’ position

Front 44

if nephrogenic cords fuse, results?

Back 44

kidneys will fuse, probably won’t be able to ascent

Front 45

if kidneys fused, which artery will prevent ascent

Back 45

interior mesenteric artery

Front 46

name four abnormalities that ureteric bud-metanephric mass interaction difficulties may cause

Back 46

bifid ureter (can remain separate right to bladder), supernumary kidneys (if branches develop far apart, can have multiple kidneys), crossed renal ectopia (ureters both grow on one side, so one kidney is crossed over), renal agenesis (metanephric mass and ureteric bud fail to interact – kidney doesn’t develop)

Front 47

contributes to amniotic fluid volume

Back 47

fetal urine

Front 48

how is amniotic fluid volume controlled

Back 48

fetus swallows it, is absorbed through fetal intestine into fetal circulation, then across placenta to maternal circulation: is cleared through maternal kidneys

Front 49

purpose of amniotic fluid

Back 49

cushion, allows fetus to grow, unconstrained limb movement, practice breathing with fluid

Front 50

practice breathing promotes

Back 50

growth/development of lungs

Front 51

too little amniotic fluid is

Back 51

oligohydramnios – causes bilateral renal agenesis (kidneys don’t develop)

Front 52

symptom of too little amniotic fluid

Back 52

too small for dates

Front 53

if too little amniotic fluid – fetal characteristics

Back 53

potters face: flat face/nose, epicanthic folds nr. eyes

Front 54

if bilateral renal agenesis, what happens

Back 54

die from pulmonary hypoplasia – lungs don’t develop

Front 55

oligohydramnios characteristics

Back 55

can’t flex limbs (not enough room) tendons too short, chest, lungs not developed, lungs not developed, don’t produce urine: usually die.

Front 56

why does oligohydramnios occur?

Back 56

fetus can’t produce urine – urine doesn’t go into amniotic fluid, so less amniotic fluid (req’d for dev.)

Front 57

def. oligohydramnios

Back 57

anything that interferes w/ urine flow to amniotic sac

Front 58

causes of oligohydramnios

Back 58

bilateral polycystic kidney disease, bilateral renal agenesis, premature rupture of amniotic membrane (leakage of fluid), posterior urethral valve (remnant of urogenital membrane)

Front 59

bladder develops from

Back 59

upper part of urogenital sinus expansion

Front 60

bladder is continuous with

Back 60

allantois

Front 61

which ducts and tubes join the urogenital sinus

Back 61

ureters, and mesonephric ducts (common excretory ducts)

Front 62

when kidneys ascend, ureters?

Back 62

are drawn cranially (ascend w/kidneys)

Front 63

upper part of urogenital sinus becomes

Back 63

bladder

Front 64

lower part of urogenital sinus becomes

Back 64

urethra

Front 65

allantois forms?

Back 65

uracus (when involutes) umbilicus-bladder remnant

Front 66

uracus forms?

Back 66

fibrous median umbilical ligament

Front 67

if problem with allantois/uracus closing?

Back 67

uracal fistula (open – urine out of umbilicus), allantois sinus (if still open near umbilicus), allantois diverticulum (if still open off bladder), cyst (if midway)

Front 68

problem with bladder development

Back 68

extrophy – mesoderm doesn’t separate bladder from sinus, body wall tears, or ureter opens to body surface: result is similar – bladder open to body wall