"Microscopic Anatomy Urinary System Ira Ames" 4/10

Question 1

List 2 hormones produced in the kidney.

Answer 1

Produces renin (influences fluid & electrolyte balance and blood pressure)
Produces erythropoietin (promotes rbc formation)

Question 2

How would define a renal lobe?

Answer 2

Renal lobe

renal pyramid plus cortical tissue overlying its base and covering its sides

Question 3

The projection of each medullary pyramid into the lumen of a minor calyx is called:

Answer 3

Renal papilla

Question 4

What components of a nephron are contained within a medullary ray?

Answer 4

Collecting tubules and collecting ducts
Medullary ray is medullary tissue that projects up into the cortex.
Straight portion of PCT enters the medullary ray.

Question 5

What is normally contained within the urinary space?

Answer 5

Urinary space is the part between the Bowman’s capsule and the glomerulus
Glomerular filtrate flows through here.

Question 6

Which component of the nephron begins at the urinary pole of Bowman’s capsule?

Answer 6

Proximal tubule

Question 7

What are the 3 components of the kidney filtration barrier?

Answer 7

1. Endothelium of glomerular capillaries fenestrated no diaphragms blocks blood cells & platelets
2. Basement membrane fusion product made by both endothelium & podocytes restricts large proteins
3. Filtration slits

Question 8

What specialization of the apical surface of the epithelium lining the proximal tubules creates the brush border?

Answer 8

Microvilli, only found in the PCT

Question 9

In which parts of the nephron are intercellular boundaries between epithelial cells not visible with the light microscope?

Answer 9

PCT AND DCT

Question 10

List the 3 parts of the loop of Henle.

Answer 10

1. Descending
2. thin (both descending and ascending)
3. Ascending

NOTE that a cross section of the thin limb resembles a cross section of a large capillary or small venule

Question 11

What are the distinguishing morphological features of the macula densa?

Answer 11

Macula densa
(modified epithelial cells in the wall of the distal tubule)
columnar epith. nuclei close together
Found next to Bowman’s capsule

Question 12

Which type of nephron has the longest thin segments of the loop of Henle?

Answer 12

Juxtamedullary nephrons

most important in the production of hypertonic urine

Question 13

The visceral layer of the glomerulus has what special kinds of cells?

Answer 13

Podocytes

Question 14

How is urine collected?

Answer 14

Collecting tubules merge to form collecting ducts which open into the minor calyx.

Question 15

How can you tell the difference between a collecting tubule and a PCT?

Answer 15

Visible and obvious intercellular boundaries in collecting tubules

Question 16

What is the diff between collecting tubule and collecting duct?

Answer 16

Duct - columnar epi

Tubule - cuboidal epi

Question 17

What are the components of the juxtaglomerular appartus?

Answer 17

Macula densa (blood osmolarity and volume sensing element)
Extraglomerular mesangial cells aka Lacis cells
Juxtaglomerular cells (produce renin)

Question 18

What are juxtaglomerular cells?

Answer 18

Modified smooth muscle cells in the tunica media of the afferent arteriole.

Question 19

What epithelium is found in the penile urethra?

Answer 19

Pseudostratified to stratified columnar, glands of Littre near the surface

Female urethra: stratified squamous with some pseudostratified columnar epith., surrounded by smooth muscle instead of erectile tissue