Histology of Renal Structures

Question 1

Organs of the Urinary system

Answer 1

• Kidneys
• Ureters
• Urinary bladder
• Urethra

Question 2

Functions of Urinary System

Answer 2

• Regulates fluid balance (fluid volume) of the body
• Excretes organic waste products & conserve nutrients
• Stabilizes pH
• Regulates ion concentrations in the blood
• Endocrine functions: Erythropoietin, Renin, ACE, Vitamin D

Question 3

The fictional unit of the kidney is…

Answer 3

The nephron

1-4 mi/kidney

Question 4

Tubular passageways associated with blood vessels

Answer 4

Proximal Convoluted Tubule
Loop Of Henle
Distal Convoluted Tubule
Collecting Duct

Question 5

Glomerulus is…

Answer 5

A specialized capillary bed attached to arterioles on both sides (maintains high pressure)

Question 6

Arterioles attached to the glomerulus are:

Answer 6

• Large afferent arteriole

* Narrow efferent arteriole

Question 7

Afferent arteriole function

Answer 7

Feeds glomerular capillary bed

Question 8

Efferent arteriole function

Answer 8

Drains glomerular capillary

bed

Question 9

Arterioles are high resistance vessels. True or false?

Answer 9

True

Question 10

How do the attached arterioles aid the glomerulus?

Answer 10

• Afferent diameter is greater than efferent diameter, so blood pressure in glomerulus is extremely high
• The high BP forces fluids and solutes out of the blood and into the glomerular capsule that drains into the collecting tubule

Question 11

Glomerular Filtration Assembly

Answer 11

1. Capillary endothelium
2. Basement
3. Glomerular epithelium

Question 12

Types of nephrons

Answer 12

2 - Cortical and Juxtamedullary

Question 13

Cortical nephrons

Answer 13

(85% of all nephrons)
Shorter
Mostly in cortex of kidney, very small portion of LOH enters medulla
Produce “standard” urine.

Question 14

Juxtamedullary nephrons

Answer 14

• 15%
• Located near corticomedullary junction
• Responsive to ADH
• Produce highly conc urine

Question 15

Juxtamedullary nephrons can concentrate urine by…

Answer 15

… creating a gradient of hypertonicity in medullary interstitium

Question 16

Types of cells in Parietal layer of Bowman’s capsule

Answer 16

Simple squamous

Question 17

Types of epithelial cells in proximal convoluted tubule

Answer 17

Cuboidal or low columnar

Question 18

The cell apex in PCT has abundant border microvilli. True or false?

Answer 18

True

Question 19

The loop of Henle is made up of thin and thick ascending and descending limbs. True or false?

Answer 19

True

Question 20

The think limbs in the loop of Henle are similar to…

Answer 20

…PCT. Cuboidal or low columnar

Question 21

Types of epithelial cells in thin limbs of loop of Henle

Answer 21

Squamous

Question 22

PCT or DCT, which is longer?

Answer 22

PCT

Question 23

DCT & PCT both found in…

Answer 23

…the cortex, lined with simple cuboidal epithelium.

Question 24

DCT cell features

Answer 24

• No brush border
• No apical canaliculi
• Smaller cells
• Elaborate basal membrane invaginations & associated mitochondria

Question 25

DCT establishes contact with...

Answer 25

...vascular pole of renal corpuscle of its parent nephron

Question 26

At what point are the PCT & afferent arteriole modified?

Answer 26

Where the DCT established contact with vascular pole of renal corpuscle of its parent nephron

Question 27

Extraglomerular mesangial, Goormaghtigh, Lacis cells or Polkissen cells are...

Answer 27

Pericytes found outside the glomerulus, near the vascular pole.

Question 28

Apart from endothelial cells & podocytes, glomerular | capillaries have...

Answer 28

...mesangial cells adhering to their walls

Question 29

Which cells have receptors for angiotensin II?

Answer 29

Intraglomerular mesangial cells

Question 30

Cell type responsible for...

Answer 30

- Production of cytokines & prostaglandins | - Synthesis of extra cellular matrix

Question 31

Intraglomular mesangial cells have receptors for...

Answer 31

ANF - vasodilator; relaxing blood flow

Question 32

Juxtaglomerular Apparatus =

Answer 32

Macula densa + Juxtaglomerular cells

Question 33

Kidneys may sustain 90% loss of nephrons and still not show apparent symptoms. True or false?

Answer 33

True

Question 34

Nephrolithiasis occurs when...

Answer 34

urine becomes too concentrated and substances crystalize. Stones begin to move down the ureter, causing pain.

Question 35

There is a progressive decline in urinary function with age. True or false?

Answer 35

True, and the bladder shrinks with aging

Question 36

Urinary retention is common in females, true or false?

Answer 36

False, males

Question 37

Length or female urethra

Answer 37

5 cm long

Question 38

Epithelium of female urethra

Answer 38

Stratified + areas of pseudostratified columnar

Question 39

Epithelium of prostatic of male urethra

Answer 39

Transitional epithelium

Question 40

Epithelium of membranous male urethra

Answer 40

Stratified/Pseudostratified columnar

Question 41

Epithelium of cells and bulbous & pendulous urethra

Answer 41

Mostly pseudostratified columnar + stratified, squamous

Question 42

Epithelium in the mucosa of the urinary bladder wall

Answer 42

Transitional epithelium: 5-6 cells thick in undistended; 3⁄4 in stretched epithelium

Question 43

Muscle fibres in the urinary bladder run...

Answer 43

...in every direction until the bladder neck is approached where 3 layers of smooth muscle are distinct

Question 44

The walls are thick & folded in an empty bladder. True or false?

Answer 44

True

Question 45

The walls of the ureters...

Answer 45

...become gradually thicker as the bladder is approached

Question 46

Peristalsis aids gravity in urine transport. True or false?

Answer 46

True

Question 47

Calyces, Renal pelvis, Ureter, bladder are lined by...

Answer 47

Transitional epithelium