Development of the Kidney

Question 1

What are the 3 stages of kidney development?

Answer 1

1. pronephros (3-4 weeks)
2. mesonephros (4weeks-2months)
3. metanephros (5 weeks-maturity)

Question 2

The kidneys develop from the _____ _____ within the _____ _____, a tissue that runs laterally and ventrally to the dorsal aorta lengthwise along the coelom of the embryo.

Answer 2

nephrogenic cord, urogenital ridge

Question 3

The pronephros and mesonephros start as a clump of cells called

Answer 3

nephrotomes

Question 4

The nephrotomes vesiculate and join to form the _____ _____

Answer 4

mesonephric duct

Question 5

The mesonephric duct grows _____ to join with the developing _____

Answer 5

caudally, cloaca

Question 6

After the mesonephric duct joins with the cloaca, it is called the _____ duct

Answer 6

Wolffian

Question 7

While the mesonephric duct is crucial in development of hte kidney, it eventually becomes ____ in males and ____ in females

Answer 7

part of the male reproductive system and degenerates in females

Question 8

The vesicular tubules of the pronephros ____ by approximately 4 weeks

Answer 8

degenerate and disappear

Question 9

In lower vertebrates such as many species of fish, the _____ functions for the entire lifetime of the animal as the kidney.

Answer 9

mesonephros

Metanephros typically develops in land-dwelling vertebrates

Question 10

What is the mullerian duct or paramesonephric duct?

Answer 10

It is a duct that develops from an invagination of the coelom wall that runs along most of the length of the Wolffian body to also join with the cloaca. This duct is the duct from which the oviducts and uterus develop in females. This duct degenerates in males

Question 11

The metanephros begins as a tiny bud of epithelial cells from a portion of the mesonephric duct where it joins with the _____. This bud is called the _____ bud

Answer 11

Cloaca, ureteric

Question 12

The ureteric bud is enveloped by a small region of cells called the _____ _____.

Answer 12

Metanephric blastema

Question 13

During development, the ureteric bud will grow lengthwise and branches will develop within the tissue of the _____ _____ to initially form the ____ and the regions of the renal pelvis and major and minor calyces.

Answer 13

metanephric blastema, ureter

Question 14

What are malpighian pyramids?

Answer 14

The regions of developing epithelia from the ureteric bud that will eventually line the calyces generate a series of epithelial-lined out-growths as tubules that run roughly parallel to each other from the medulla into the cortical regions of the kidney. These tubules are called malpighian pyramids.

Question 15

The ureteric bud branches during kidney development in several stages to give rise to what?

Answer 15

Ureters

Renal pelvis

Calyces

Collecting ducts

Collecting tubules

Question 16

The epithelia of the malpighian pyramids become the ____ _____. They branch and give rise to short branching tubules that become the ____ _____.

Answer 16

collecting ducts, collecting tubules

Question 17

What is the metanephric spheroid?

Answer 17

It is a cluster of metanephric mesodermal cells that is at the tips of the collecting tubules (originating from the metanephric blastema)

Question 18

The metanephric spheroids vesiculate to form a _____ _____.

Answer 18

Metanephric vesicle

Question 19

What is the metanephric tubule?

Answer 19

The metanephric vesicle elongates and forms a short tubule which folds in on itself in the shape of the letter “S”. This is the metanephric tubule which eventually forms the rest of the epithelium of the nephron

Question 20

When does the blood supply of the kidneys develop?

Answer 20

During the development and elaboration of the tissues derived from the ureteric bud, the renal artery and vein begins to supply the developing metanephric blastema. These branch in between the malpighian pyramids as the intralobar vessels, giving rise to the arcuates, interlobular vessels, the glomerular capillaries, efferent arterioles, and vasa recta.

Question 21

What is the urogenital sinus?

Answer 21

The cloaca is where the hindgut and developing mesonephric duct and allantois all join. When the hindgut leaves the cloaca, the two separate structures are now the urogenital sinus and the rectum.

Question 22

The kidney proper develops from the _____ _____

Answer 22

ureteric bud