Histology and Embryology

Question 1

which germ layer is the kidney and bladder derived from

Answer 1

mesoderm

Question 2

what are the 3 nephric stages of kidney development and which stages are functional

Answer 2

pronephros
mesonephros - function between weeks 6-10 then regress
metanephros - becomes the permanent kidney

Question 3

what forms the metanephrons

Answer 3

ureteric bud

metanephric blastema

Question 4

what becomes the collecting system

Answer 4

the ureteric bud

Question 5

what does the collecting system consist of

Answer 5

Ureter
Renal Pelvis
Major calyces
Minor calyces
1-3 million Collecting Ducts

Question 6

what does the metanephric blastema become

Answer 6

the nephron

Question 7

what is the nephron and its function

Answer 7

Functional unit of the Kidney

Filtration of blood and production of urine

Question 8

where do the kidneys develop before they ascend to there final position

Answer 8

pelvic region

Question 9

what is pelvic kidney

Answer 9

when one kidney fails to ascend

Question 10

what is horseshoe kidney

Answer 10

Inferior poles of Metanephroi meet and fuse before ascent

– kidney trapped beneath IMA

Question 11

what is the bladder formed from

Answer 11

the cloaca (hindgut endoderm)

Question 12

what is Bladder Exstrophy

Answer 12

skin over the lower abdominal wall does not form properly.

The bladder is open and exposed on the outside of the abdomen

Question 13

what is the kidney covered by

Answer 13

thin but strong capsule of dense collagen fibres

Question 14

where is the site of entry of renal artery and exit of renal vein and ureter

Answer 14

the hilum

Question 15

going from kidney to ureter

Answer 15

1 - renal pelvis
2 - major calyces
3 - minor calyces

Question 16

position of the medulla

Answer 16

divided into medially pyramids, with apices pointing towards the hilum (called the papillae) ending on the minor calcyces

Question 17

what is the nephron composed of

Answer 17

the renal corpuscle and renal tubules

Question 18

what is the renal corpuscle formed from

Answer 18

group of capillaries called the glomerulus and the Bowman’s capsule

Question 19

what is bowman’s capsule

Answer 19

cup of simple squamous epithelium at the blind end of the nephron which the capillaries invaginate

Question 20

what separates the blood from the glomerular filtrate

Answer 20

2 cell layers

• capillary endothelium
• podocytes

Question 21

what are podocytes

Answer 21

specialised epithelium which lies on top of the glomerular capillaries
has pores

Question 22

what is between the two cell layers

Answer 22

thicker than usual basal lamina

Question 23

what is the role of mesangial cells

Answer 23

produce a connective tissue core called the mesangium

help removal of debris

Question 24

histology of loop of henle

Answer 24

simple squamous lining in which the nuclei typically protrude into the lumen
transition to the thick ascending limb, which is lined by a simple cuboidal epithelial cells with abundant mitochondria

Question 25

what is the named given to the blood vessels that dip down into the medulla from above and then climb back up to the cortex

Answer 25

vasa recta

Question 26

where are the distal convoluted tubule found and what are they lined by

Answer 26

found in the cortex

lined by simple cuboidal epithelium

Question 27

what is the difference between proximal and distal conducted tubules

Answer 27

DCT lack a brush border of extensive microvilli

Question 28

what are medullary rays

Answer 28

collecting ducts + proximal and distal tubules together in parallel bundles running perpendicular to the surface of the kidney

Question 29

what is the lining of collecting ducts

Answer 29

simple columnar epithelium

Question 30

what is the Juxtaglomerular Apparatus

Answer 30

• specialized structure formed by the distal convoluted tubule and the glomerular afferent arteriole.
• its main function is to regulate blood pressure and the filtration rate of the glomerulus

Question 31

what is the Juxtaglomerular Apparatus composed of

Answer 31

The macula densa.
The juxtaglomerular cells.
The extraglomerular mesangial cells (or lacis cells)

Question 32

what cells secrete renin and where are they found

Answer 32

Juxtaglomerular cells

found in the afferent arteriole

Question 33

where is urine produced at the renal papilla collected

Answer 33

minor calyx, flows into the major calyx, renal pelvis, ureter and then into the bladder.

Question 34

what are almost all of the conducting parts of the urinary tract lined with

Answer 34

transitional epithelium or urothelium

Question 35

what domed cells are at the luminal surface of transitional epithelium

Answer 35

umbrella cells

Question 36

what is below the epithelium

Answer 36

lamina propria

Question 37

what is the female urethra composed of

Answer 37

transitional epithelium which transition to stratified squamous near its termination

Question 38

what is the each part of the male urethra composed of

Answer 38

prostatic urethra - transitional epithelium

membranous urethra - transitional epithelium changes to stratified columnar.

penile urethra - stratified columnar epithelium which near the tip of the penis becomes stratified squamous.