Kaplan Physio

Question 1

Extracellular Volume: When there is a net gain of fluid by the body, this compartment always _____

Answer 1

enlarges

Question 2

ICF = what % of TBW

Answer 2

2/3

Question 3

Concentration of solutes is the equivalent to

Answer 3

body osmolality

Question 4

At steady-state, the intracellular concentration of water equals the _________concentration of water (remember the cell membrane is not a barrier for water).

Answer 4

extracellular

Question 5

ECF = what % of TBW

Answer 5

1/3

Question 6

what controls volume regulation?

Answer 6

Aldosterone and ADH

Question 7

Intracellular fluid volume is determined by Extracellular fluid osmolality. We change the _______ first then this changes the _______

Answer 7

We change the extracellular volume first then this changes the intracellular volume

Question 8

ECF is made up of

Answer 8

• 3/4 = interstitial fluid (ISF)

- 1/4 = plasma volume (PV)

Question 9

Intracellular volume is only altered if ________

Answer 9

extracellular osmolality changes

Question 10

if ECF osmolality increases, cells ______ water and _____

Answer 10

if ECF osmolality increases, cells lose water and shrink

Question 11

the greater the [solute] the ___ the [water] will be

Answer 11

the greater the [solute] the LOWER the [water] will be

Question 12

• If the overall osmolarity doesn’t change then you had an _____ fluid loss
• ex)
• causes

Answer 12

• If the overall osmolarity doesn’t change then you had an ISOTONIC fluid loss
• ex) hemorrhage, diarrhea, vomiting
• causes decrease in BP, increase in RAAS and increase in ADH

Question 13

A net loss of body fluid ______ extracellular volume

Answer 13

decreases

Question 14

• ex) of a hypotonic fluid loss

- a consequence of a hypotonic fluid loss

Answer 14

• ex) sweating/respiration
• ex) hypotonic urine in DI (decrease in ADH could be cause)
• decrease BP
• increase RAAS and ADH

Question 15

the intracellular and ____________ osmolalities are the same at steady-state

Answer 15

extracellular

Question 16

effect of giving a hypertonic saline

Answer 16

• increase BP

- decrease RAAS, ADH

Question 17

Loss of isotonic fluid, what happens to:

• ECF Vol
• ICF Vol
• Body osmolarity
• ex)

Answer 17

• decrease ECF
• no change ICF
• no change osmolarity
• hemorrhage, diarrhea, vomiting

Question 18

intracellular volume varies with the effective osmolality of the _______ first. EX)

Answer 18

extracellular compartment first. i.e. sweating, diarrhea, fluid resuscitation, etc

Question 19

Loss of hypotonic fluid, what happens to:

• ECF Vol
• ICF Vol
• Body osmolarity
• ex)

Answer 19

• decrease ECF
• decrease ICF
• Increase osmolarity
• dehydration, DI, Alcoholism

Question 20

Gain of isotonic fluid, what happens to:

• ECF Vol
• ICF Vol
• Body osmolarity
• ex)

Answer 20

• increase ECF
• no change in ICF
• no change in osmolarity
• isotonic saline given

Question 21

Gain of hypotonic fluid, what happens to:

• ECF Vol
• ICF Vol
• Body osmolarity
• ex)

Answer 21

• increase ECF
• decrease ICF
• decrease osmolarity
• hypotonic saline, water intoxication

Question 22

if ECF osmolality decreases, cells _____ water and ____

Answer 22

if ECF osmolality decreases, cells gain water and swell

Question 23

RAAS stands for

Answer 23

renin angiotensin aldosterone system

Question 24

Gain of hypertonic fluid, what happens to:

• ECF Vol
• ICF Vol
• Body osmolarity
• ex)

Answer 24

• increase ECF
• decrease ICF
• increase osmolarity

Question 25

On a D-Y diagram what do the compartments represent?

Answer 25

• right of the center black line (Y-axis) = ECF
• left of the center black line (Y-axis) = ICF
• top of diagram (horizontal line intersecting Y-axis) = osmolarity.

Question 26

What are 2 primary factors that stimulate aldosterone

Answer 26

1. Plasma angiotensin II (stimulates aldosterone release)

2. Plasma K+ (stimulates aldosterone release)

Question 27

Aldosterone

Answer 27

• increases Na+ reabsorption in principal cells of kidney
• Na+ reabsorption plays a key role in regulating ECV
• regulates plasma K+ and increases the secretion of K+ in principal cells

Question 28

angiotensinogen is converted to ___ by___

Answer 28

angiotensinogen is converted to ATI by renin

Question 29

ATI is converted to ___ by ___

Answer 29

ATI is converted to ATII by ACE

Question 30

ADH stimulates water reabsorption in principal cells of the kidney via

Answer 30

via the V2 receptor

• by regulating water ADH plays a pivotal role in regulating EC osmolality
• ADH also vasoconstrictor arterioles (V1 receptor)
• thus can serve as a hormonal regulator of vascular tone

Question 31

primary regulators of ADH are

Answer 31

1. plasma osmolality (directly related): increase stimulates, decrease inhibits
2. BP/Vol (inversely related): increase inhibits; decrease stimulates
3. (CRH) Corticotropin releasing hormone (directly related)
4. Angiotensin II (directly related)

Question 32

3 primary regulators of renin

Answer 32

1. perfusion pressure to kidneys, reflex sympathetic stimulation (inversely related): increase inhibits; decrease stimualtes
2. sympathetic stimulation to the kidney (direct effect via beta-1 receptors)
3. Na+ delivery to the macula densa (inversely related): increase inhibits, decrease stimulates

Question 33

ADH

Answer 33

• stimulates water reabsorption in principal cells of the kidney
• via the V2 receptor
• by regulating water ADH plays a pivotal role in regulating:
• EC osmolality
• ADH also vasoconstricts arterioles (V1 receptor)
• thus can serve as a hormonal regulator of vascular tone

Question 34

if ECF [sodium] increases, what happens to the ICF

Answer 34

if ECF [sodium] increases, ICF volume decreases

- if if ECF [sodium] decreases, ICF volume increases

Question 35

normal extracellular osmolality

Answer 35

approx 290 mOsm/kg (Osmolarity of 290 mOsm/L)

Question 36

the main factor promoting filtration

Answer 36

capillary hydrostatic pressure

Question 37

the main factor promoting absorption

Answer 37

plasma protein osmotic force