05.05 - Homeostasis (Rao) - Lecture, no reading

Question 1

Formula for Plasma Osmolarity

Answer 1

(2 x Na mM) + (Glucose mOsm) + (Urea mOsm)

Question 2

Major cation in ICF

Answer 2

K+

Question 3

What happens to normal RBC when placed in solution of Low Pna and High Glycerol

Answer 3

Initially shrinks, then swells

Question 4

Probes for Total Body Water

Answer 4

2H2O, 3H2O, Antipyrene

Question 5

Major extracellular anion

Answer 5

Cl-

Question 5

Is Cl- greater in plasma or interstitial fluid

Answer 5

Greater in interstitial fluid (Gibbs Donnan Effect)

Question 5

Formula for BV

Answer 5

BV= PV/(1-Hct)

Question 6

Probe for measuring ECFV

Answer 6

Inulin, Thiosulfate, Na+

Question 8

Major cation in ECF

Answer 8

Na+

Question 9

Is HCO3- greater in ICV or ECV

Answer 9

ECV

Question 9

Is PO4+ greater in ICV or ECV

Answer 9

ICV

Question 10

How does Infusion of Isotonic Salt Solution change ECF and ICF

Answer 10

Increase ECF, no change in ICF

Question 11

Formula for ICF

Answer 11

ICF = TBW - ECF

Question 12

Is SO4+ greater in ICV or ECV

Answer 12

ICV

Question 12

Permeability of Na, Urea, Water, Glycerol across PM

Answer 12

Im, Per, Per, Slowly permeable

Question 14

What causes Gibbs Donnan Effect?

Answer 14

Proteins impermeable to PM - Anionic so bind Na in plasma and repel Cl- into interstitial fluid

Question 16

Is Cl greater in ICV or ECV

Answer 16

ECV

Question 16

How do you correct for filtration/excretion in calculating ECF

Answer 16

Subtract excreted value from numerator

Question 17

Ca2+ in ICF vs ECF

Answer 17

None in ICF

Question 18

Is Na greater in plasma or interstitial fluid

Answer 18

Plasma (Gibbs Donnan Effect)

Question 19

Formula for ISF (interstitial)

Answer 19

ISF = ECF - PV

Question 21

What percent of Blood is plasma vs rbc

Answer 21

60% plasma, 40% rbc

Question 21

If probe is metabolized, will it over or underestimate the volume

Answer 21

Overestimate

Question 23

What to look for when elevated Osmolarity Gap

Answer 23

Missing Osmotic particle

Question 24

2 Major anions in ECF

Answer 24

Cl-, HCO3

Question 25

3 Major anions in ICF

Answer 25

Protein, Bicarb, Phosphate

Question 27

If probe is synthesized, will it overestimate or underestimate volume?

Answer 27

Underestimate

Question 28

What Osmolarity gap is abnormal

Answer 28

\>10

Question 29

What percent of water intake is from food + drink

Answer 29

88%

Question 30

Is Mg greater in ICV or ECV

Answer 30

ICV

Question 31

What percent of TBW is BV

Answer 31

8%

Question 32

Formula for PV with probe

Answer 32

PV = Q / Conc.

Question 33

Why is Inulin good probe for ECFV

Answer 33

Smaller than Albumin, can diffuse across capilary wall but not PM

Question 34

Probe for measuring PV

Answer 34

131 I-Albumin, Evans blue dye