Urinary System part 1

Question 1

What are the functions of the urinary system?

Answer 1

• maintenance of water and electrolyte homeostasis
• regualtion of acid-base balance
• excretion of metabolic waste products
• production of renin and erythropoietin
• conversion of vitamin D
• regulation of calcium balance

Question 2

What does renin do?

Answer 2

blood pressure control

Question 3

What does erythropoietin do?

Answer 3

stimulates red blood cell production in the bone marrow

Question 4

What is the order of blood supply to the kidney?

Answer 4

1. 5 segmental lobar arteries per kidney
2. interlobar artery
3. arcuate artery
4. intralobular artery
5. Afferent arteriole

Question 5

What layer of the kidney are the afferent glomerular arterioles found?

Answer 5

cortex

Question 6

The peritubular capillary network (PCN) arises from ____________ __________

Answer 6

efferent arterioles

Question 7

__________ _________ drain the glomeruli and form capillary networks

Answer 7

Efferent arterioles

Question 8

What are the two main components of the nephron?

Answer 8

renal corpuscle
renal tubule

Question 9

What is the functional unit of the kidney?

Answer 9

nephron

Question 10

What is the function of the renal corpuscle?

Answer 10

filters blood plasma

Question 11

What is the function of the renal tubule?

Answer 11

modifies filtrate to form urine

Question 12

The nephron is composed of…

Answer 12

• renal corpuscle
• proximal convoluted tubule
• loop of henle
• distal convoluted tubule
• collecting tubule/duct

Question 13

What are the capillaries around the proximal and distal convoluted tubules?

Answer 13

peritubular capillaries

Question 14

What is the name of the capillary network around the loop of henle?

Answer 14

vasa recta (arterial and venous)

Question 15

What are the two types of nephrons?

Answer 15

-cortical
— subcapsular (short)
— midcortical (intermediate)
-juxtamedullary (long loops)

Question 16

What does the difference between nephron types depend on?

Answer 16

location in the cortex and the length of the loop of henle

Question 17

What is the blood flow to the kidneys from the heart and back again?

Answer 17

• aorta
• renal artery
• afferent arteriole (skipped some steps)
• glomerular capillaries
• efferent arteriole
• peritubular capillaries or to the vasa recta
• venules
• veins
• renal vein
• inferior vena cava

Question 18

What is the path that filtrate/urine takes through the kidney and out of the body?

Answer 18

• bowman’s space
• proximal convoluted tubule
• loop of henle (desending, thin ascending, thick ascending)
• distal convoluted tubule
• collecting duct
• minor calyces
• major calyces
• renal pelvis
• ureter
• urinary bladder
• sphincter
• urethra

Question 19

Where are the raw materials gathered in the kidney?

Answer 19

Bowman’s space

Question 20

Where do the “bulk operations” happen in the kidney?

Answer 20

Proximal convoluted tubule

Question 21

Where does the “fine tuning” (reabsorbtion) occur in the kidney?

Answer 21

distal convoluted tuble and collecting duct

Question 22

Where does the “planning ahead” and concentration of the interstitum occur in the kidney?

Answer 22

loop of henle

Question 23

What cells make up the visceral layer on the glomerulus?

Answer 23

podocytes

Question 24

What cells make up the parietal layer of the renal corpuscle?

Answer 24

simple squamous epithelium

Question 25

What separates the visceral layer and parietal layer of the renal corpuscle?

Answer 25

bowman's space (urinary space)

Question 26

What makes up a vascular pole in the kidney?

Answer 26

Afferent and Efferent arteriole

Question 27

What are the functions of the mesangial cells in the kidney?

Answer 27

- secrete the mesangial matrix - secrete vasoactive factors and cytokines - remove trappped residues and aggregated protein from BM (keep filter free of debris) - changing te filtration pressure of glomerulus (contractile properties)

Question 28

What are the main components of the mesangial matrix?

Answer 28

collagen type IV laminin fibronectin proteoglycans

Question 29

______________ ________ cells found between the afferent A and Efferent A towards the vascular pole

Answer 29

Extraglomerular mesangial

Question 30

____________ _______ cells are located inside the glomerulus in between the capillaries

Answer 30

Intraglomerular mesangial

Question 31

What three things make up the filtration barrier? (she said this would prolly be on the test)

Answer 31

1. fenestrated capillary endothelium 2. basal lamina (basement membrane) 3. podocytes of the visceral layer of bownman's capsule

Question 32

What three things make up the filtration barrier? (so important it is on here twice!)

Answer 32

1. fenestrated capillary endothelium 2. basal lamina 3. podocytes of the visceral layer

Question 33

What are the characteristics of glomerular capillaries?

Answer 33

- fenestrated - large pores - permeable to water, urea, glucose, and small proteins - barrier only to formed elements in blood and large macromolecules

Question 34

What are glomerular capillaries permeable to?

Answer 34

water, urea, glucose, and small proteins

Question 35

The lamina rarae (basal lamina) contains?

Answer 35

type IV collagen laminin fibronectin negatively-charged proteoglycans

Question 36

What is the average gap between podocyte foot projections (pedicels)?

Answer 36

25 nm

Question 37

What molecules pass freely through the podocytes (visceral layer)?

Answer 37

- water, ions, and small organic molecules cross freely - peptide hormones and small proteins cross reasonably freely

Question 38

What are the pedicles (foot processes) separated by?

Answer 38

filtration slits

Question 39

What are the filtration slits between foot processes (pedicles) covered by?

Answer 39

slit diaphragm

Question 40

What protein makes up the slit diaphragm in the kidney?

Answer 40

nephrin

Question 41

What is the function of the pedicels and filtration slits?

Answer 41

acts as a barrier to large macromolecules, proteins, negatively charged molecules, and blood cells

Question 42

What is the filtration process before reaching the proximal convoluted tubule?

Answer 42

- blood enters glomerulus (afferent arterioles) - arteriole pressure forces fluid through fenestrae - large molecules are trapped by basal lamina - negatively charged molecules are stopped by basal lamina and podocytes - fluid passes thorugh pores in slit diaphragm to enter urinary space (proximal convoluted tubule)

Question 43

Where are proximal convoluted tubules found in the kidney?

Answer 43

ONLY in cortex

Question 44

What does the proximal convoluted tubule do?

Answer 44

- primary site of water resorption - removes 75% of water and ions (Na, Cl)

Question 45

What does the lumen of the proximal convoluted tubule have?

Answer 45

microvilli and brush border

Question 46

How do Na, Cl, and H2O move in the proximal convoluted tubule?

Answer 46

Na - active transport Cl - passive transport H2O - small transmembrane channel