Concentrating Urine PP#3

Question 1

What system is a mechanism for controlling blood pressure and fluid volume?

Answer 1

Renin Angiotensin System

Question 2

A fall in BP releases what?

Answer 2

Renin

Question 3

Renin converts angiotensinogen into _________?

Answer 3

Angiotensin 1

Question 4

Where is angiotensin 1 converted to angiotensin 2?

Answer 4

Lungs

Question 5

What substance converts angiotensin 1 into angiotensin 2?

Answer 5

ACE

Question 6

Angiotensin 2 is a potent ________?

Answer 6

Vasoconstrictor

Question 7

How does angiotensin 2 work?

Answer 7

• Directly on kidneys to cause salt and water retention

- Stimulates Aldosterone

Question 8

What 3 things stimulate the renin angiotensin system?

Answer 8

• Drop in BP
• Drop in fluid volume
• Increase Beta 1

Question 9

Where is angiotensin made?

Answer 9

Liver

Question 10

Where is renin made?

Answer 10

Juxtaglomerular apparatus of the Kidney

Question 11

What 3 things inhibit Renin angiotensin system?

Answer 11

• increase in BP
• Increase in fluid volume
• Decrease in Beta 1

Question 12

4 components of juxtaglomerular apparatus

Answer 12

• Afferent smooth muscle
• Efferent Smooth Muscle
• Mesangial cells
• Macula Densa Cells

Question 13

Macula densa cells detect what?

Answer 13

Sodium in the distal tubule

Question 14

What is the most potent vasoconstrictor known?

Answer 14

Angiotensin 2

Question 15

5 roles of angiotensin 2

Answer 15

• Vasoconstriction
• Increased aldosterone
• Increased ADH
• Increased thirst
• Feedback inhibition of renin

Question 16

Aldosterone acts where?

Answer 16

Distal tubules and collecting ducts

Question 17

2 Aldosterone functions?

Answer 17

Decrease K

Increase Sodium

Question 18

What does aldosterone stimulate?

Answer 18

Na / K ATPase pump

Question 19

What is Conn’s syndrome?

Answer 19

Too much aldosterone

Question 20

What causes Conn’s syndrome?

Answer 20

Aldosterone secreting tumors

Question 21

Most dangerous effect of Conn’s syndrome

Answer 21

Hypokalemia

Question 22

What does hypokalemia cause?

Answer 22

Hyperpolarization of nerve and muscle cells

Question 23

Why is it important to be able to concentrate urine?

Answer 23

Maintain osmolarity for proper cell function

Question 24

The human kidney can produce a max urine concentration of what?

Answer 24

1200-1400 mosm

Question 25

What is the minimum amount of urine a human needs to produce per day to excrete waste?

Answer 25

0.5 Liters or 600 mOsm

Question 26

What other name is ADH known by?

Answer 26

Vasopressin

Question 27

Where is ADH made

Answer 27

Hypothalmus

Question 28

Where is ADH stored

Answer 28

Pituitary

Question 29

What is ADH primary role?

Answer 29

Conserving H2O by concentrating urine

Question 30

What 2 receptors stimulate ADH?

Answer 30

Osmoreceptors

Mechanoreceptors

Question 31

What inhibits ADH release?

Answer 31

ETOH

Question 32

How does ADH work

Answer 32

↑ permeability of collecting ducts to water

Question 33

What happens to tubular fluid in the collecting duct when ADH is present?

Answer 33

H2O is allowed to leave and urine is more concentrated

Question 34

Urea consists of what?

Answer 34

2 ammonia moleccules

Question 35

Urea is a by product of what?

Answer 35

amino acid metabolism

Question 36

How much urea is made per day?

Answer 36

25-30g

Question 37

Where is urea made?

Answer 37

Liver

Question 38

Urea play an important role in generating a _______ interstisium

Answer 38

Hypertonic

Question 39

Urea contributes what % of renal medulla osmolarity?

Answer 39

40%

Question 40

The TAL is ________ to water and urea

Answer 40

Impermiable

Question 41

Urea passively diffuses from collecting ducts to medulla only when what substance is present?

Answer 41

ADH

Question 42

What are the 2 functions of the Vasa Recta?

Answer 42

• remove fluid from interstitium

- Minimize solute uptake

Question 43

What characteristic of medulla blood flow minimizes solute loss?

Answer 43

Sluggish flow