02: Histology

Question 1

Each nephron consists of (X) and its associated tubules. What is (X) comprised of?

Answer 1

X = renal corpuscle

1. Bowman’s capsule
2. Glomerular capillaries

Question 2

The urinary space is between (X) and (Y) and contains (Z).

Answer 2

X = bowman's capsule
Y = cap's of glomerulus
Z = ultrafiltrate

Question 3

(X) turns into a renal tubule at (Y) portion of the renal corpuscle.

Answer 3

X = Bowman's capsule
Y = urinary pole

Question 4

At which point does the ultrafiltrate become filtrate? And urine?

Answer 4

Filtrate in tubules; urine when it enters minor calyx

Question 5

(X) cells compose the visceral layer of Bowman’s capsule. Together with (Y), an important filtration barrier is formed that’s selective for which molecule characteristics?

Answer 5

X = podocytes
Y = endothelial basal lamina

Size and charge

Question 6

Glomerular filtration slits are composed of:

Answer 6

Interdigitated pedicels of adjacent podocytes

Question 7

T/F: A membranous slit diaphragm spans the filtration slits of glomerulus.

Answer 7

False - non-membranous diaphragm

Question 8

Slit diaphragm consists of (X) proteins, critically involved in (Y).

Answer 8

X = extracellular and transmembrane (esp nephrin)
Y = passage of proteins (i.e. albumin) into urinary space

Question 9

(X) cells take on role of CT support of glomerular structure. What are the two types of (X) cells?

Answer 9

X = mesangial

1. Extraglomerular (i.e. lacis)
2. Intraglomerular

Question 10

(Intra/extra)-glomerular mesangial cells are (X), thus capable of altering blood flow through glomerulus. List some other functions they have.

Answer 10

Intraglomerular;
X = contractile

Phagocytosis and repair (immune interaction)

Question 11

3 compartments in the glomerulus:

Answer 11

1. Vascular (arterioles and cap’s)
2. CT (mesangial cells, basement membranes, cortical interstitium)
3. Urinary space (continuous with lumen of PCT)

Question 12

T/F: Mesangial cells are responsible for collagen production.

Answer 12

True

Question 13

Glomerulus: Why is the filtration barrier’s basement membrane so (thin/thick)?

Answer 13

Thick;

Shared by podocytes and cap endothelium

Question 14

T/F: Glomerular capillary endothelium is continuous and covered by podocytes.

Answer 14

False - fenestrated

Question 15

Ultrafiltrate contains:

Answer 15

1. water
2. glucose
3. ions
4. AA
5. small molecules (under 68 kD)
6. urea

Question 16

Collecting ducts are found in (cortex/medulla).

Answer 16

Both

Question 17

Thick descending and thick ascending tubule found in (cortex/medulla).

Answer 17

Medulla

Question 18

PCT has the same morphology as (X) tubule. How can you tell them apart?

Answer 18

X = thick descending

Location (cortex v. medulla)

Question 19

Squamous cells with few organelles is characteristic of (X) renal tubule and suggestive of primarily (Y) transport in this segment.

Answer 19

X = thin 
Y = passive (water resorption)

Question 20

Cuboidal/pyramidal cells with long microvilli and many basal infoldings is characteristic of (X) renal tubule. Which function do these tubules have?

Answer 20

X = proximal convoluted and thick descending;

Large molecule and active resorption

Question 21

Thick ascending and distal tubules have which general function?

Answer 21

Active salt transport

Question 22

Water resorption under hormonal control is a function of (Y) tubules.

Answer 22

Y = collecting ducts

Question 23

Kidney release of Renin eventually causes (increase/decrease) in water resorption. Through which series of steps?

Answer 23

Increase;

Increase in angiotensin production, increase in ADH release from pituitary, and ADH makes collecting ducts more permeable to water

Question 24

Collecting tubules can be distinguished from DT by (X) cells. What is the structure/function of (X) cells?

Answer 24

X = interacalated “dark”

“Dark” due to abundant mitochondria (also golgi, polyribosomes, H+/HCO3 transporters);
Modulate acid-base balance

Question 25

Which cells in collecting ducts are responsive to ADH? What exactly does ADH do?

Answer 25

Principal cells; | Activates aquaporins, increasing permability to and resorption of water

Question 26

Collecting ducts converge in (cortex/medulla) to from (X) which open into (Y).

Answer 26

Base of medulla; X = ducts of Bellini Y = minor calyces

Question 27

T/F: Each segmental artery, branching off of renal artery, supplies unique region of kidney.

Answer 27

True

Question 28

Most, (X)% of glomeruli are (cortical/juxtamedullary).

Answer 28

X = 75 | Cortical

Question 29

T/F: Cortical nephrons from cortical glomeruli never reach medulla.

Answer 29

False - reach only outer medulla

Question 30

Peritubular cap plexus drains into (X). Vasa recta drains into (Y).

Answer 30

``` X = interlobular veins directly or stellate veins first Y = interlobular veins or directly into arcuate veins ```

Question 31

List the three components of the Juxtaglomerular apparatus.

Answer 31

1. Macula densa 2. JG cells 3. Mesangial cells

Question 32

Macula densa is localized near (X) vessel. It functions to monitor (Y) and regulate (Z).

Answer 32

``` X = afferent arteriole Y = NaCl conc in DCT Z = renin secretion ```

Question 33

(X) cells contain renin granules.

Answer 33

X = JG

Question 34

JG cells are formed from (X) layer of (Y) vessels.

Answer 34

``` X = tunica media Y = arterioles ```

Question 35

(X)% of cortex is interstitium. (Y)% of medulla is interstitium.

Answer 35

``` X = 10 Y = 40 ```

Question 36

T/F: Fibroblasts are present in both cortex and medulla.

Answer 36

True

Question 37

T/F: Fibroblasts in cortex secrete EPO and prostaglandin.

Answer 37

False - secrete EPO, but fibroblasts in medulla secrete prostaglandin

Question 38

T/F: Lymphocytes are only found in medullary interstitium.

Answer 38

False - in cortex too

Question 39

You'd find high osmolarity interstitium in (cortex/medulla).

Answer 39

Medulla

Question 40

T/F: There is a muscularis mucosae layer in bladder.

Answer 40

True

Question 41

Transitional epithelium in bladder, aka (X), have which sensory function(s)?

Answer 41

X = urothelium 1. Mechanosensation 2. Chemosensation

Question 42

List the three layers of the transitional epithelium in bladder. Star the common host site for UTIs.

Answer 42

1. Umbrella cells* 2. Intermediate layer 3. Basal cell layer

Question 43

T/F: Umbrella cell layer of urothelium has gap junctions between cells.

Answer 43

False - tight junctions

Question 44

T/F: Basal cell layer of urothelium hosts the stem cells.

Answer 44

True

Question 45

T/F: Intermediate layer of urothelium is in contact with basal lamina.

Answer 45

True - via fine cytoplasmic projections

Question 46

Distally, urethra epithlium transitions from (X) to (Y) types.

Answer 46

``` X = transitional Y = stratified squamous ``` In between, may be pseudostratified