Exam 2 Lecture - Development of the Urogenital System

Question 1

Where is the urogenital ridge found?

Answer 1

in the dorsal part of the embryologic kidney

Question 2

What are the 3 attempts to make the kidney called?

Answer 2

pronephros
mesonephros
metanephros

Question 3

Where does the pronephric attempt occur?

Answer 3

most cranial attempt; in the neck

Question 4

What does the pronephric attempt become?

Answer 4

the mesonephric duct

Question 5

How does the mesonephros attempt of the kidney degrade?

Answer 5

once it reaches its maximum size, it degenerates from cranial to caudal

Question 6

What does the mesonephros attempt become in the adult?

Answer 6

in the male, the caudal tubules and duct remain to form testicular channels, epididymis and ductus deferens

Question 7

What is the metanephros?

Answer 7

the attempt of kidney creation that becomes the adult kidney

Question 8

What structures create the adult kidney?

Answer 8

the metonephric diverticulum and the metonephrogenic mass

Question 9

Where is the metonephric diverticulum located?

Answer 9

comes off of the mesonephric duct

Question 10

What does the metonephric diverticulum differentiate the surrounding mesoderm into?

Answer 10

the metanephrogenic mass

Question 11

What does the metanephrogenic mass give rise to?

Answer 11

the urine conducting part of the kidney (functional unit)

-ureter, renal pelvis, calyxes and collecting ducts

Question 12

How are nephrons formed?

Answer 12

metanephric diverticulum causes areas within the metanephrogenic mass to differentiate into renal vesicles which will transition into metanephric tubules which creates nephrons

Question 13

True or false: the animal cannot regrow a nephron

Answer 13

true

Question 14

What cases variations in kidneys between species?

Answer 14

the differences between interactions of the metanephrogenic mesenchyme and the metanephric diverticulum

Question 15

What does the bladder develop as an extension of?

Answer 15

the urachus and the cranial end of the urogenital sinus

Question 16

What does the urogenital sinus become in the male?

Answer 16

pelvic urethra and penile urethra

Question 17

What does the urogenital sinus become in the female?

Answer 17

pelvic urethra, vestibule and the caudal vagina

Question 18

In early development, what does the mesonephric duct go into?

Answer 18

it goes directly into the bladder

Question 19

What does the mesonephric duct become in the adult?

Answer 19

the ductus deferens in males

Question 20

What does the metanephric diverticulum become in the adult?

Answer 20

the ureter

Question 21

How does the mesonephric duct and the metanephric diverticulum become in the correct places that they should be in the adult?

Answer 21

the bladder grows dorsally so that the future ureter and ductus deferens empty into it separately, and then differential growth causes them to switch places so that the ureter empties into the bladder and the ductus deferens empties into the urethra

Question 22

renal agenesis

Answer 22

lack of development

Question 23

dysplasia

Answer 23

abnormal development of the kidney

Question 24

hypoplasia

Answer 24

underdevelopment

Question 25

ectopic kidneys

Answer 25

the kidney could be sitting in the pelvic cavity

Question 26

patent urachus

Answer 26

when the urachus does not close right after birth and urine still flows through the allantoic cavity

Question 27

ectopic ureter

Answer 27

not opening in the correct location

Question 28

When is genetic sex determined?

Answer 28

at fertilization

Question 29

What structures are present during indifferent development?

Answer 29

mesonephric duct and paramesonephric duct

Question 30

What structure gives rise to male structures?

Answer 30

mesonephric duct

Question 31

What structure gives rise to female structures?

Answer 31

paramesonephric duct

Question 32

What suppresses the paramesonephric duct in males?

Answer 32

the mullerian inhibiting substance

Question 33

What is the role of testosterone in males?

Answer 33

stimulate the mesonephric duct to create the ductus deferens and epididymis and stimulates the growth of the external genitalia

Question 34

What is the role of estrogen in females?

Answer 34

- stimulate paramesonephric duct to create the uterine tube, uterus, cranial portion of the vagina - stimulate the formation of external genitalia (labia, clitoris, and caudal portion of vagina)

Question 35

How do germ cells migrate into the genital ridge?

Answer 35

-leave the yolk sac at about 100-300 cells and migrate into the embryo via the hind gut, through the mesentery, and into the genital ridge

Question 36

What are the gondal cords formed by?

Answer 36

disintegrating mesonephric tubules

Question 37

What do the mesonephric tubules become?

Answer 37

the seminiferous tubules, rete testis, efferent ductus

Question 38

What does the mesonephric duct become?

Answer 38

ductus deferens, epididymis

Question 39

In early development what is the function of the gubernaculum?

Answer 39

it just tethers the testicle in place

Question 40

What type of tissue is the gubernaculum?

Answer 40

mesenchymal type tissue

Question 41

How does the gubernaculum function?

Answer 41

hyaluronic acid brings water into the gubernaculum causing it to swell, then cells of the gubernaculum remove the acid causing it to shrink, bringing the testicle into the scrotum

Question 42

What are the remnants of the gubernaculum?

Answer 42

the ligament of the tail of epididymis and the proper ligament of the testes

Question 43

How are the follicles of the ovary created?

Answer 43

degenerating mesonephric tubules move into the area of development, forming the gonadal cords, the oocytes move into the gonadal cords, the oocytes begin to separate and create follicles

Question 44

What does the paramesonephric duct give rise to?

Answer 44

uterine tube, uterine horn, body, cervix, part of the vagina

Question 45

What does the urogenital sinus become?

Answer 45

part of the vagina, the vestibule

Question 46

vagina and uterus duplex

Answer 46

no fusion between the paramesonephric ducts; found in marsupials

Question 47

vagina simplex uterus duplex

Answer 47

single vagina with two uteri and two cervial canals; found in rabbits or rodents

Question 48

uterus bicornis

Answer 48

two horned, fusion of the duct creates the body of the uterus; found in the horse

Question 49

What does the genital tubercle become in the male?

Answer 49

glans penis, corpora cavernosa penis, corpus spongiosum penis

Question 50

What does the genital tubercle become in the female

Answer 50

clitoris

Question 51

What do the urogenital folds become in the male?

Answer 51

ventral aspect of the penis

Question 52

What do the urogenital folds become in the female?

Answer 52

the labia of the vulva

Question 53

What do the labioscrotal swellings become in the male?

Answer 53

scrotum

Question 54

What do the labioscrotal swellings become in the female?

Answer 54

does not really develop into anything in domestic species

Question 55

What is the anal genital distance?

Answer 55

the distance between the anus and where the tubercle ends up

Question 56

When is the anal genital distance greater?

Answer 56

when the species is exposed to testosterone

Question 57

Genital malformation: hypolasia

Answer 57

result of few or no germ cells

Question 58

Genital malformation: cryptorchidism

Answer 58

retaining testicle on one or both sides

Question 59

Genital malformation: stenosis of the ducts

Answer 59

abnormal fusion

Question 60

Genital malformation: hypospadia

Answer 60

open urethra

Question 61

Free martin

Answer 61

In dizygotic twins that share a blood supply; female is the most effected (suppression of paramesonephric duct derivatives)