Urinary System

Question 0

List the arterial supply to the kidney.

Answer 0

• renal arteries
• segmental arteries
• interlobar arteries
• arcuate arteries
• interlobular arteries
• afferent arterioles
• glomerulus
• efferent arterioles

Question 1

What are the four functions of the urinary system?

Answer 1

1. Filter blood
2. Produce, store and excrete urine
3. Regulate blood & interstitial fluid volume (& blood pressure)
4. Red blood cell production

Question 2

Name the 4 tissue layers surronding the kidney from deepest to most superficial.

Answer 2

1. Fibrous capsule
2. Perinephric fat
3. Renal fascia
4. Paranephic fat

Question 3

What are the three main processes that occur in the nephron to form urine?

Answer 3

1. Filtration
2. Reabsorption
3. Secretion

Question 4

How do you differentiate between cortical and juxtamedullary nephrons? Which is more common?

Answer 4

Cortical nephrons: The bulk of the nephron’s structures reside in the kidney cortex

Juxtamedullary nephrons: their long nephron loops extend deep into the medulla

Cortical nephrons are most common (85%)

Question 5

What are the tubular components of a nephron?

Answer 5

1. Proximal Convoluted Tubule
2. Loop of Henle
3. Distal Convoluted Tubule

Question 6

What capillary networks surround the tubules of a nephron?

Answer 6

1. Peritubular Capillaries

2. Vasa Recta

Question 7

What are the two main components of the renal corpuscle?

Answer 7

1. Glomerulus

2. Glomerular Capsule

Question 8

What are the components of the filtration membrane?

Answer 8

1. Fenestrated Endothelium
2. Basement Membrane
3. Filtration Slits

Question 9

How do podocytes help the nephron accomplish its goal of blood plasma filtration?

Answer 9

The podocytes have pedicel “feet” that wrap around the glomerular capillaries but do not completely ensheath them. Tiny gaps called filtration slits allow filtrate to leak out of the blood plasma.

Question 10

What is the primary function of the proximal convoluted tubule?

Answer 10

Cells in the PCT reabsorb almost all nutrients leaked through the filtration membrane.

Question 11

Trace the pathway of filtrate (reabsorbed into peritubular capillaries) back to the heart.

Answer 11

PCT > Peritubular Capillaries > Interlobular Vein > Arcuate Vein > Interlobar Vein > Renal Vein

Question 12

What is the primary function of the Loop of Henle?

Answer 12

Reabsorption of water and solutes

Question 13

What is the primary function of the distal convoluted tubules?

Answer 13

Secretes Potassium and Hydrogen ions from the peritubular capillaries into tubular fluid.

Question 14

What is the primary function of the collecting duct?

Answer 14

Concentrates urine

Question 15

What are the components of the juxtaglomerular appartatus (JA)? Why is the JA important?

Answer 15

1. Juxtaglomerular cells
2. Macula Densa

It works to regulate blood pressure.

Question 16

What type of tissue is each JA cell derived from?

Answer 16

They are modified smooth muscle cells of the afferent arteriole.

Question 17

What type of epithelial cells make up each region of the nephron?

Answer 17

Renal Corpuscle - simple squamous
PCT - simple cuboidal epithelium
Loop of Henle - simple cuboidal and simple squamous
DCT - simple cuboidal
Collecting Duct - simple cuboidal/simple columnar

Question 18

Describe the microscopic anatomy of the ureters (eg. tuincs and cell types)

Answer 18

The wall of the ureter has three layers:

1. Mucosa
2. Muscularis - 2 layers - inner longitudinal, outer circular
3. Adventitia

Question 19

Describe the microscopic anatomy of the bladder.

Answer 19

Four tunics:

1. Mucosa - with rugae
2. Submucosa
3. Muscularis - Detrucer muscle, 3 layers
4. Adventitia

Question 20

What kind of epithelium lines the ureters and the bladder lumen?

Answer 20

Transitional epithelium

Question 21

Where in the body will you find rugae?

Answer 21

Stomach and bladder

Question 22

What is the function of the urethra? What sphincters control the release of urine?

Answer 22

To propel urine outside the body; Internal urethral sphincter and external urethral sphincter.

Question 23

What kind of epithelium do you expect to find in the urethra?

Answer 23

stratified squamous epithelium