Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Embryology US > Development of urinary system > Flashcards

Development of urinary system Flashcards

You may prefer our related Brainscape-certified flashcards:
U.S. Geography flashcards
1
Q

The kidneys, ureters & trigone of urinary
bladder develop from the———-while the rest of urinary
bladder & urethra develop from the —————–

A

intermediate mesoderm

endoderm of the urogenital sinus (cloaca)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q 
The development of the kidneys in the
human embryo occur in ---- successive,
overlapping kidney systems, which are:
•----------
•---------
•---------
A

3
Pronephros
Mesonephros
Metanephros

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q
  • ————-It is the 1st & simplest kidney system which appear in the embryo.
  • Site:
  • Structure:
  • Function:
  • Fate:
A

PRONEPHROS
• It is developed in the cervical part of intermediate mesoderm (early in 4th week), as series of 7-10 solid masses of cells, called ➔ nephrotomes.

• These masses form a 7-10 excretory tubules called pronephric tubules
(one tubule from each segment of intermediate mesoderm).
• These tubules end medially into coelomic cavity, where each tubule
overlies a tuft of capillaries, “external glomerulus”.
• Each tubule ends laterally by joining the lateral end of next one ➔ a longitudinal collecting duct called pronephric duct, which extends to open into the cloaca, by 24th day

  • No function in the human embryo. Thus, the pronephros is rudimentary & non functioning, analogous to kidney of some fish.
  • The tubules degenerate completely by the end of the 4th week, while the pronephric duct persists to become the mesonephric duct.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

•Excretory tubules of the pronephric and mesonephric systems in a ———weekold embryo

A 
intermediate mesoderm 
nephrogenic cord
pronephros
mesonephros.
5
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q 
• -----------: is formed by an
invagination of small branch of dorsal
aorta into coelomic cavity ➔ --------------, or into wall of nephric tubules
➔ --------------
• Excretory unit = --------- + nephric
tubule.
A 
The glomerulus
external
glomerulus
internal glomerulus.
glomerulus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the site of Mesonephros ?structure?

A

• It extends from lower cervical to upper lumbar segments of the intermediate mesoderm
• Each segment of the intermediate mesoderm develops 2-3 or more of excretory tubules called “mesonephric tubules (There are about
70 nephrotomes on each side).
• These tubules are not connected with intraembryonic coelum. Each
tubule is S-shaped that has:
• Medial end: acquires a glomerulus, where it forms a Bowman’s
capsule, which is invaginated by capillary tuft, internal
glomerulus.
• Lateral end: opens into the longitudinal mesonephric (Wolffian) duct, which opens caudally into primitive urogenital sinus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

• In middle of ——- nd month, the mesonephros forms a large —– swelling (urogenital ridge) on sides of midline, attached dorsally
by a broad urogenital mesentery.
• The developing gonad lies medial to the mesonephros.

A

2

ovoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the fate of mesonephros ?

A 
• While caudal tubules still
formed: cranial ones & their
glomeruli start to
degenerate.
• The majority of the tubules
disappear by end of 2
nd
month, while a few tubules
persist near the gonads.
• The mesonephric duct
disappears in the female,
while in the male it forms the
vas deferens.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the fate of Mesonephric tubules in male ?

A

◼ The upper tubules degenerate.
◼ The middle & lower tubules form the efferent
ductules of testis, head of epididymis & paradidymis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the fate of Mesonephric tubules in female ?

A 
◼ Degenerates, few
rudimentary tubules
remain forming the
epoophoron &
paroophoron in the broad
ligament.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the fate of Mesonephric duct in male ? 6

A 
It gives: male ducts
◼ Body & tail of epididymis.
◼ Vas deferens.
◼ Ejaculatory duct.
◼ Seminal vesicle.
◼ Ureteric bud.
◼ Trigone of the bladder.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is the fate of Mesonephric duct in female ?3

A

It gives:
◼ Ureteric bud.
◼ Trigone of the bladder.
◼ A rudimentary duct called Gartner’s duct.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

in —————-Situated in cervical and upper

thoracic regions

A

Pronephros

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

in ————Consists of 7-8 segmentally

arranged pronephric tubules

A

Pronephros

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q 
in -----------Each tubule is provided with one
external glomerulus; sometimes
both external and internal
glomeruli are connected with the
tubule
A

Pronephros

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

in ————- Each tubule is connected to the
coelomic cavity by- a peritoneal
funnel

A

Pronephros

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

————-Situated in lower thoracic and

lumbar regions

A

Mesonephros

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

—————Consists of 70-80 non-segmental

mesonephric tubules

A

Mesonephros

19
Q

—————Each tubule is provided with one

internal glomerulus only

A

Mesonephros

20
Q

————The mesonephric tubules are not

connected to the coelomic cavity

A

Mesonephros

21
Q

• ————- It is the 3rd kidney system (permanent kidney) to
develop.

A

Metanephros

22
Q

Site of Metanephros ?

A

it arises in lower lumbar

& sacral regions.

23
Q

Metanephros
• Structure: it appears in ——week, during regression of the mesonephros. It has a double origins:
•———————-:
• Begins at 28th day as an
outgrowth from —————wall
of mesonephric duct close to cloaca
➔ metanephric (ureteric) diverticulum.
➢ This diverticulum ——— &——— metanephros, which forms a cap on its distal end.
➢ The elongated stem will form the
———- its end dilates to form the
————— The later divides into
cranial & caudal branches (future
major calyces). Each subdivides until
more than ———- generations of collecting tubules are formed (— - —- millions).
➢ The 2nd order ——–&——– 3rd&4th generations to form the minor calyces by 7th week.
➢ The collecting tubules (10-25tubules) of 5th & successive generations elongate, converge on a minor calyx to form the ————–

A 
5th 
Ureteric bud (collecting system)
dorso-medial 
elongates-penetrates
ureter
primitive pelvis
12
1-3
enlarges & absorbs
renal pyramid
24
Q

• Metanephric cap = metanephric blastema = renal vesicle = metanephric vesicle
(excretory system):
o While the collecting tubules penetrate the —————, the end of each one is covered by ——————- (in the form of a cell cluster).
o The cap moves with tubule distally and forms a cell cluster on each side of it. They form —————, which develop into small tubules (nephrons /
excretory tubule):
o Its proximal end invaginated by
————–, glomerulus(forming the —– capsule).
o Its distal end opens into
collecting tubule
o Continuous lengthening of the nephron gives proximal convoluted tubule, ———– & distal convoluted tubule.

A 
metanephric blastema
metanephric tissue cap
renal vesicles
capillary loop
Bowman ’s
loop of Henle
25
Q

• Ascent & rotation of kidney:
• The metanephros shifts cranially, between 6
th-9th week, due to ———————, growth of lumbar & sacral regions & elongation of ureter.
• At first, it is supplied by ————- branches of aorta, then by —————- branches.
• Its hilum directed ventrally at first then rotates medially.
• The kidney is lobulated, then lobulation ———— during 1st year of life.
• The metanephros is functional during 10-13th week, and the urine passes to amniotic cavity (in renal agenesis, there is ———————).
• Urine formation begins towards the end of the first trimester of fetal development and is excreted into the amniotic fluid

A 
diminution of body curvature
pelvic
abdominal
disappears
oligohydramnios
26
Q
  • Urogenital sinus:
  • From 4-6th week, the primitive urogenital sinus is formed by growth of————— septum, which meats the cloacal membrane at the ——————.
  • The sinus is closed by the —————– & is divided by the entrance of mesonephric ducts, into:
  • —————- part: It is the larger part above mesonephric ducts. It is continuous with allantois. It gives rise to:
  • Urinary bladder, except the —————
  • Upper ½ of prostatic urethra in male & whole urethra in female
A 
urorectal
perineal body
urogenital membrane
 Vesico-urethral
trigone.
27
Q

• Definitive urogenital sinus: lies below ducts & is subdivides into:
• ——– part: is narrow canal, it gives the lower ½ of prostatic urethra &
membranous urethra in male.
• ———— part: is flattened from side to side, closed by urogenital membrane, it gives most of phallic (penile) urethra in male.
N.B.: in female, the whole definitive urogenital sinus gives rise to —————–.

A

Pelvic
Phallic
vestibule of vagina

28
Q

Development of urinary bladder
• It develops from:
•———– part: ————– in origin. Apex connected by allantois to umbilicus. Proximal part of allantois incorporated into ————-. Distal part
narrowed into thick fibrous cord, ——– which gives median umbilical ligament after birth.
•Caudal parts of mesonephric ducts: ——— in origin. During division of cloaca, their proximal parts absorbed into bladder wall, forming trigone of bladder

A 
Vesico-urethral
Endodermal
bladder
urachus
Mesodermal
29
Q
  • Ureters, initially emerging from mesonephric ducts, enter bladder separately. Later, ureteric orifices move ———-; those of ducts move medially, become close together to enter prostatic urethra. Absorbed parts incorporate into the trigone of bladder, i.e. mesodermal. Rest of bladder is ————–.
  • ———– lining of trigone is replaced by endodermal epithelium, so the bladder becomes lined completely by epithelium of endodermal origin.
  • Splanchnic mesoderm around cloaca gives————
A

cranially
endodermal
Mesodermal
muscle wall

30
Q

•Development of urethra: (in male)
•Prostatic part:
•Upper ½: From ————part
(endodermal). Its post wall develops from
absorbed ———-(mesodermal).
•Lower ½: From pelvic part of definitive ————–
•Membranous part: From pelvic part of
definitive urogenital sinus. It gives two
endodermal outgrowths, the —————-
•Spongy (penile) part: From ————- part of
definitive urogenital sinus & ———– overlying glans penis.

A 
vesico-urethral 
mesonephric ducts 
urogenital sinus.
bulbo-urethral glands.
phallic
ectoderm
31
Q

Anomalies of kidney
————————Bilateral / unilateral, due to early
degeneration of ureteric bud. Unilateral agenesis
occurs 1:1500, more in males. Bilateral agenesis
associated with oligo-hydramnios, incompatible with
life (transplantation)

A

Renal agenesis:

32
Q

Anomalies of kidney
———————-Due to inadequate
branching of ureteric bud.

A

Hypoplasia of kidney

33
Q

Anomalies of kidney
————————-Nephrons are abnormally
developed; consist of primitive ducts lined by
undifferentiated epithelium surrounded by thick
layers of connective tissue.

A

Dysplasia of kidney

34
Q

Anomalies of kidney
——————Results from extra-ureteric
bud

A

Supernumerary kidney

35
Q

• Solitary or polycystic, due to non-union of a collecting tubule with an
excretory tubule. Urine accumulated in excretory tubule causes its
dilatation, followed by cyst formation, lined by cuboidal epithelium.
Usually present in renal cortex.
• Cysts may arise from abnormal development of collecting system, due
to hyperplasia of their walls or abnormal differentiation of ureteric bud
leads to dilatation, constriction or atretic tubules.

A

• Congenital cystic kidney:

36
Q 
Anomalies of kidney
------------------------
1:600. Lower
poles fuse together, usually located at
lower lumbar vertebrae. Its ascent
prevented by inferior mesenteric
artery. Ureters arise from anterior
surface of kidney, pass ventral to
isthmus.
A

Horse-shoe kidney:

37
Q

Anomalies of kidney
—————Caused by fusion
of upper & lower poles of both kidneys.

A

Rosette kidney

38
Q

2 examples of Anomalies of kidney?

A
  • Pelvic kidney

* Lobulated kidney

39
Q

Anomalies of ureters
—————————-• One ureter ends in bladder, other ends into vagina, urethra or
vaginal vestibule or into prostatic urethra, ejaculatory duct, vas
deferens or seminal vesicle.
• Due to migration of one ureter downward with its mesonephric duct
to open abnormally.

A

• Ectopic ureter

40
Q 
Anomalies of ureters
-----------------------------------
• Due to splitting of ureteric
bud, may be partial (bifid) or
complete (cap may be
divided).
• In bifid (Y-shaped) ureter:
contractions in its limbs may
be asynchronous ➔ reflux of
urine from one limb to other;
i.e. stasis of urine & infection.
A

• Double ureter:

41
Q

Anomalies of urinary bladder
• Urachal fistula, cyst & sinus:

  • Fistula: Persistence of ——————
  • Cyst: Persistence of——————
  • Sinus: Persistence of its ———–
A

allantois
localized part.
distal (umbilical) end

42
Q 
Anomalies of urinary bladder
-----------------------
• Bladder opens on the surface
of anterior abdominal wall, due
to failure of development of
infra umbilical part of
abdominal wall.
A

• Ectopia vesica:

43
Q

• Urethra opens into dorsum of
the penis

A

Epispadias

44
Q

• Urethra opens into ventral
surface of the penis

A

Hypospadias

Embryology US (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions