urinary/renal system 5

Question 1

Where does blood leave and enter the glomerulus

Answer 1

Enters through afferent arteriole

Leaves through efferent arterioles

Question 2

What percentage of cardiac output goes to renal

Answer 2

20-25% of cardiac output (CO)

1-1.2 L/min

Question 3

What is glomerular filtration determined by

Answer 3

Forces - Pressure gradients
Permeability of glomerular capillary
Surface area of glomerular capillary

Question 4

What are the 4 forces that determine net filtration pressure

Answer 4

Glomerular hydrostatic pressure (GHP)
Blood colloid osmotic pressure (BCOP)
capsular hydrostatic pressure (CsHP)
capsular colloid osmotic pressure (CsCOP)

Question 5

What does clearance (Cs) equal

Answer 5

Cs = Us x V / Ps

mL/min

Question 6

What is GFR

Answer 6

Glomerular Filtration Rate - amount of fluid filtered per unit time

Question 7

Describe the GFR

Answer 7

Tightly regulated
Variation from person to person
Declines slowly from age 30

Question 8

What must a substance be to be used as a measure of GFR

Answer 8

Not be reabsorbed from tubule
Not be secreted into tubule
Not be metabolised

Question 9

What two main substances fit the bill for measuring GFR

Answer 9

Inulin - not found in body - polysaccharide not metabolised by body
Creatinine - Already in body - Waste product produced in muscles