Anatomy urinary final 3

Question 1

What is the adverage glomerular filtration rate? (filtrate produced each minute)

Answer 1

Amount of filtrate produce each minute = average of 125 mL/minute

Question 2

What three things is glomerular filtration rate controled by?

Answer 2

Autoregulation
Autonomic regulation
Hormonal control

Question 3

Glomeruli produce about ___ liters of filtrate each day.

What percent is reabsorbed?

Answer 3

180

99%

Question 4

What is Autoregulation

Answer 4

Autoregulation = local control of blood flow, ensures adequate GFR due to smooth muscle in walls of arterioles and glomerular capillaries

(keeps an adverage glomerular filtration rate)

Question 5

Renal autoregulation operates at a wide range of mean arterial pressure what is this pressure?

Answer 5

(80-160 mm Hg) to maintain constant GFR in spite of fluctuations in systemic blood pressure

Question 6

What is released as a result of an acute drop in systemic blood pressure?

What does this substance override in the kidney?

What is this processes called?

Answer 6

1. Norepinephrine
2. overrides autoregulation at the kidney level
3. Sympathetic activation

Question 7

what does GFR stand for

Answer 7

glomerular filtration rate

Question 8

what is the purpose of vasoconstriction

Answer 8

Powerful vasoconstriction reduces GFR and filtrate volume

Question 9

what regulates GFR?

Answer 9

GFR regulated by renin-angiotensin-aldosterone system

Question 10

What are the triggers for release of renin by JGC

Answer 10

Drop in blood pressure at glomerulus

Sympathetic stimulation of JG cells

Drop in osmotic pressure of fluid in collecting duct

Question 11

What snowball effects do renin have?

Answer 11

1. Renin causes release of angiotensin I
2. Angiotensin I converts to angiotensin II
3. angiotensin II constricts peripheral capillaries and triggers aldosterone secretion from adrenal glands
4. increased blood volume, increased blood pressure, and increased GFR

Question 12

What is the purpose of The renin–angiotensin-aldosterone system (RAAS)?

2. How is it different from (RAS)

Answer 12

hormone system that regulates blood pressure and fluid balance.

2. Its not different just another name

Question 13

Know that

Answer 13

When renal blood flow is reduced, juxtaglomerular cells in the kidneys convert the precursor – prorenin, already present in the blood into renin and secrete it directly into the circulation. Plasma renin then carries out the conversion of angiotensinogen, released by the liver, to angiotensin I. Angiotensin I is subsequently converted to angiotensin II by the angiotensin-converting enzyme (ACE) found in the lungs. Angiotensin II is a potent vasoconstrictive peptide that causes blood vessels to narrow, resulting in increased blood pressure.[3] Angiotensin II also stimulates the secretion of the hormone aldosterone[3] from the adrenal cortex. Aldosterone causes the renal tubules to increase the reabsorption of sodium and water into the blood, while at the same time causing the excretion of potassium (to maintain electrolyte balance). This increases the volume of extracellular fluid in the body, which also increases blood pressure.

Question 14

Countercurrent Multiplication- Exchange between fluids moving in opposite directions

Answer 14

Na and Cl are actively pumped out of thick ascending limb, increasing the osmolarity of peritubular interstitial fluid
This results in osmotic flow of water out of thin descending limb, concentrating solutes in tubular fluids
Increased osmolarity of tubular fluids promotes Na and Cl transport from ascending limb (cycle)