Urinary System Development

Question 1

What germ layer gives rise to the urogenital ridge?

Answer 1

intermediate mesoderm

Question 2

How many kidneys develop from each nephrogenic cord?

Answer 2

3

Question 3

what are the names of the 3 early kidneys?

Answer 3

pronephros, mesonephros, and metanephros

Question 4

What becomes the functional kidney in adult mammals?

Answer 4

metanephros

Question 5

What do the tubules of the mesonephros and pronephros drain into?

Answer 5

the pronephric and mesonephric duct

Question 6

describe the similar development of pronephros and mesonephros

Answer 6

nephrogenic cord segments into tubules that drain into duct, tubules eventually disintegrate

Question 7

What do mesonephric tubules surround?

Answer 7

glomeruli - vascular proliferation produced by branch of dorsal aorta

Question 8

What does the mesonephric duct persist as in the adult?

Answer 8

the epididymis and ductus deferens

Question 9

Where does the metanephros originate in the body and where does it move to?

Answer 9

originates in pelvic region and moves cranially into abdomen

Question 10

What are the 2 sources the metanephros originates from?

Answer 10

ureteric bud and metanephrogenic mass

Question 11

What does the ureteric bud develop into?

Answer 11

ureter, renal pelvis, and collecting ducts

Question 12

What does the metanephrogenic mass develop into?

Answer 12

nephrons

Question 13

What forms cell cords in early nephron formation?

Answer 13

mesodermal cells of the metanephrogenic mass

Question 14

what do cell cords in the metanephrogenic mass become?

Answer 14

metanephric tubules and eventually nephrons

Question 15

what happens at the ends of a metanephric tubule in nephron formation?

Answer 15

one end surrounds a capillary glomerulus to become a glomerular capsule and the other end connects to a collecting duct

Question 16

What are the 3 characteristic regions of a nephron?

Answer 16

proximal segment, thin loop, distal segment

metanephric tubule differentiates into these

Question 17

What divides the cloaca?

Answer 17

the urorectal septum

Question 18

what does the dorsal cloaca become?

Answer 18

rectum, anal canal, and anal membrane (anus)

Question 19

what does the ventral cloaca become?

Answer 19

urogenital sinus and urogenital membrane (urogenital orifice)

Question 20

what is the urachus and where does it attach?

Answer 20

it’s the intraembryonic stalk of the allantois and it attaches to the cranial urogenital sinus

Question 21

what creates the trigone region?

Answer 21

the mesonephric duct and ureter openings switch places. The ureters move cranially and leave behind longitudinal muscles.

Question 22

What becomes the urethra?

Answer 22

the caudal urogenital sinus

cranial is bladder

Question 23

Describe female urethra development

Answer 23

mid urogenital sinus becomes urethra

caudal urogenital sinus becomes vestibule

Question 24

Describe male urethra development

Answer 24

mid urogenital sinus becomes pelvic urethra

caudal urogenital sinus becomes elongated penile urethra

Question 25

What is hydronephrosis?

Answer 25

an abnormality where nephrons fail to communicate with the collecting tubules

Question 26

What is patent urachus?

Answer 26

an abnormality where the allantoic stalk doesn’t close at birth, urachus becomes bladder pouch

Question 27

What is an ectopic ureter?

Answer 27

an abnormality where ureter enters urethra or vagina, incontinence