Embryology - Urogenital System

Front 1

what germ layer and embryonic structure do kidneys develop from?

Back 1

intermediate mesoderm - nephrogenic ridge

Front 2

intermediate mesoderm, which lies between the______ and the _____.

Back 2

1. lateral plate mesoderm

2. somites (paraxial mesoderm)

Front 3

intermediate mesoderm later loses its connection with the somites and forms longitudinal elevation of mesoderm called the _______.

Back 3

nephrogenic ridge

Front 4

nephrogenic ridge forms three systems

Back 4

1. Pronephros
2. Mesonephros
3. Metanephros

Front 5

mesonephros is smallest in ?

type of placenta ?

Back 5

carnivores (endotheliochorial),


endotheliochorial: type of placenta in which the maternal blood is separated from the chorion by the maternal capillary endothelium; occurs in dogs.

Front 6

Name 3 parts of Urogenital sinus (formed below urorectal septum)

And what they form?

Back 6

1. vesicle part (cranial) : forms urinary bladder

2. pelvic part (middle): Pelvic urethra, Prostate in males

Pelvic urethra and Vagina (caudal) in females

3. phallic part (phallic)
- forms Penile urethra and Bulbourethral gland in male
- Vestibule and Vestibular gland in female

Front 7

how does intermediate mesoderm emerge? how created?

how is nephrogenic ridge created from interm.mesoderm?

Back 7

- emerges as individual segments, 1 associated with each somite
(on both sides of notocord, b/c there are somites on each side also)

segments of interm.mesoderm fuse to form ridge
-

Front 8

What is fate of each "system" (3) of nephrogenic ridge in mammals?

Back 8

pronephros - forms first but regresses (except in fish)
- only main duct persists as duct of mesonephros

mesonephros - 2nd to form. Functional only in fetus, dev. little farther than pronephr. b/c each meson.tubule actually forms a fetal glomerulus
- later regresses except duct part which forms male genital duct and also to form metanephric diverticulum

metanphros - last to grow. It dev. all the way and becomes adult kidney

Front 9

Mesophrose is largest in ____?
Intermediate size in ____?
Smallest in ____?

Bonus: also name type of placenta

Back 9

Pig - largest (epitheliochorial)
Ruminant
Carnivores - smallest (endotheliochial)

for whatever reason, it is associated with type of placenta and size of connection to mother

Front 10

parts of metanephros (metanephric kidney)?

Back 10

duct actually called (1) mesonephric duct, b/c it is remnant from mesonephros

(2) UTERIC BUD aka metanephritic diverticulum develops as loop from meson.duct

(3) metanephritic. cap (outside part) kind of forms bubble around uterine bud.

Front 11

1. WHAT is metanephric diverticulum a diverticulum of? (in other words what structure does it come from?

2. -Ureteric bud (metanephric diverticulum) forms?

Back 11

1. WHAT is metanephric diverticulum a diverticulum of?
>MESOnephric duct (which is only part of mesonephros that persisted)

2. Ureteric bud (metanephric diverticulum) forms?
>collecting system and URETER

Front 12

1. Metanephric cap develops from induction of surrounding tissue and develops INTO what structure?

2. Metanephric diverticulum develops into what structures?

Back 12

1. M. cap forms Bowman’s capsule, PCT, loop of henle, and DCT.

2. Metanephric diverticulum (aka ureteric bud) develops into collecting system
-collecting tubules, major and minor calyces, renal pelvis and URETER

Front 13

How is developing urinary system and external genitalia seperated from developing rectum?
(in dork talk: partitiion of cloaca & development of bladder)

Back 13

Formed when urorectal septum moves caudally

Front 14

Urinary bladder is formed from

Back 14

left over proximal part of allantois (and vesicular part of urogenital sinus)

Front 15

Identity compartments created by urorectal partition? (2)

note: 1 of them has 3 parts

Back 15

Dorsally: rectum and anal canal

Ventrally: urogenital sinus

3 parts of urogenital sinus?
1. vesicle part (cranial)
2. pelvic part (middle)
3. phallic part (phallic)

Front 16

1. splanchnic mesoderm is closer to

2. somatic mesoderm is closer to

Back 16

endoderm

remember splanchnic means "visceral"

2. ectoderm

Front 17

Urachus forms from?

What does it become?

(don't think about it, just memorize)

Back 17

Regressed part of allantois (not bladder; see image)

Medial ligament of the bladder

Front 18

Renal agenesis

Back 18

absence of one or both kidney

Front 19

Horse-shoe kidney

Back 19

two kidneys may fuse

Front 20

Cystic kidney

Back 20

failure of union between the developing nephron and collecting tubules.

Front 21

In males, the ductus deferens and epididymis develop from the ?

Back 21

mesonephric duct

After mesophric (fetal) kidney regresses, mesen.duct hooks up with testes. Meanwhile, paramesonephric duct regresses in males.

Front 22

In female, uterine tube, uterus, and part of vagina originate from?

Back 22

paramesonephric duct

After mesonephric (fetal) kidney and mesen.duct regress, paramesonephric duct extends caudally - forming uterus/vagina in the process.

Front 23

fate of mesonephric duct in female?

fate of mesonephric duct in male?

Back 23

regresses

ductus deferens, epididymis, vesicular gland

Front 24

condition where ureter opens into the urethra (instead of bladder)? Common in female dogs.

Back 24

Ectopic ureter

Front 25

Medial ligament of the bladder known as?

Back 25

Urachus

Front 26

Urinary bladder is derivative of ?

Back 26

ventral urogenital sinus: (edit)
Vesicle part

Front 27

Pelvic urethra is derivative of ?

Back 27

ventral urogenital sinus: (edit)
Pelvic part

Front 28

Glomerulus develops from what structures?

Back 28

Glomerulus is derived from a series of branches of dorsal aorta invaginated in the bowman’s capsule BUT all blood vessels come from SPLANCHNIC MESODERM (lateral mesoderm)

So Bowman's capsule and tubular system is from INTERMEDIATE MESODERM

Front 29

another name for paramesonephric duct?

Back 29

Mullerian Duct

Front 30

another name for mesonephric duct?

Back 30

Wolffian ducts

Front 31

Testes and ovaries derived from?

Back 31

Intermediate mesoderm - gonadal ridges

Front 32

primordial germ cells originate from the ____ ;

they migrate to and induce the _____ to form ______.

Back 32

primordial germ cells originate from YOLK SAC (yolk sac endoderm);

they migrate/induce the GENITAL RIDGE to form primitive sex cords in mesenchyme (future sex cells e.g. sperm&egg).

Front 33

Which chromosome contains the testis determining factor (TDF) genes?

Back 33

Y chromosome contains the testis determining factor (TDF) genes

So in absence of this factor, female development is established (by default)

Front 34

Mullerian inhibitory substance (MIS) produced by _____, and causes ________.

Back 34

Mullerian inhibitory substance (MIS) produced by the SERTOLI cells, and causes the regression of the Mullerian (paramesonephric) duct .

Remember Mullerian duct becomes the uterus,etc.

Front 35

Testosterone produced by ?

Stimulates the development of ?

Back 35

Testosterone, produced by LEYDIG cells,
- stimulates the development of the Wolffian (mesonephros) duct and causes the regression of the Mullerian duct.

mesonephros = male

Front 36

What do the primordial germ cell develop into in the male?

Back 36

gonocytes, later spermatogonia

Front 37

What do the testis (gonadal) cords develop into?

Back 37

Seminiferous tubules Rete testis

Front 38

What is the term for accumulation of the fluid within the two layers of the tunica vaginalis?

Back 38

Hydrocoele

Front 39

How many pairs of pronephric tubules form at the nephrogenic ridge?

Back 39

7-8 pairs

Front 40

What does the remainder of the allantois degenerate into?

Back 40

Urachus

Front 41

What is the indifferent stage during development?

Back 41

When you can not determine the sex of the embryo

Front 42

What induces the genital ridge to form the primitive sex cords in the mesenchyme?

Back 42

primordial germ cells

Front 43

What do the gonadal cords in females break up into?

Back 43

Follicles which contain primordial germ cells to develop oogonia

Front 44

What do some of the persisting mesonephric tubules develop into in the male?

Back 44

efferent ductules

Front 45

What does the paramesonephric duct develop into in the male?

Back 45

Uterus masculinus

Front 46

What does the pelvic part of the urogenital sinus become in the male adult?


What does the pelvic part of the urogenital sinus become in the female adult?

Back 46

Pelvic urethra
Prostate


Urethra
Vagina (caudal)

Front 47

What does the phallic part of the urogenital sinus become in the male adult?

Back 47

Penile urethra
Bulbourethal gland

Front 48

What does the phallic part of the urogenital sinus become in the female adult?

Back 48

Vestibule
Vestibular gland

Front 49

What does the gebernaculum become in the adult male?

Back 49

Ligament of the testis and epididymis

Front 50

What does the gebernaculum become in the adult male?

Back 50

Ligament of the testis and epididymis

Front 51

What does the gebernaculum become in the adult female?

Back 51

Round ligament of the uterus

Front 52

What does the urogenital fold in the adult male become?

Back 52

urethral fold of the penile urethra

Front 53

What does the genital swelling in the adult male become?

Back 53

STROTUM

note: also (like other parts of urogenital system) originates from intermediate mesoderm

Front 54

What does the genital swelling in the adult female become?

Back 54

Labia

Front 55

What does the genital tubercle in the adult male become?

Back 55

Penis

Front 56

What does the genital tubercle in the adult female become?

Back 56

CLITORIS

Front 57

What animals have the smallest mesonephros? Type of placenta?

Back 57

Carnivores, endotheliochorial

Front 58

What does the pronephric duct continue as later?

Back 58

mesonephric duct

Front 59

What animals have the largest mesonephros? type of placenta?

Back 59

Pigs, Epitheliochorial

Front 60

What cells in the testis are derived from mesenchyme?

Back 60

Sertoli and Leydig cells

Front 61

What do the gonadal cords in females break up into?

Back 61

Follicles which contain primordial germ cells to develop oogonia

Front 62

Which cells in the ovary are of mesenchymal origin?

Back 62

follicular cells

Front 63

What does the urogenital fold in the adult female become?

Back 63

Labia minora

Front 64

What does external genitalia originate from?

Back 64

External genitalia are derived from three different swellings (mesoderm proliferations) that appear in the perineal region