Exam 1 - Lecture 2 8/26 Flashcards
Intracellular fluid % of total body water? Where is it?
Inside the cell, 2/3rds TBW
Hydrophilic
Water loving, charged i.e. K+, Na+, Cl-
Hydrophobic
Water hating, uncharged i.e. fat cells/lipids
Will drugs behave the same with a normal pH?
No!
Soluble
Ions (electrolytes), Proteins (the parts exposed to water), Carbs (glucose), some gasses such as CO2, buffers to keep pH within defined parameters, Some drugs
Insoluble
Cholesterol, steroid hormones, lipids, Some drugs i.e. propofol, nitrous gas
What do drugs need to work in the body if they are insoluble?
A carrier
What % of TBW is ECF and where is it?
1/3rd of TBW, outside the cells. Plasma and interstitial fluid (between cells)
Can blood proteins cross capillary membrane?
No, they are too big. They need to stay within the cardiovascular system (plasma).
What is the plasma composed of?
Water, proteins, and electrolytes.
What’s the ratio of plasma to ECF?
1/5 - 1/4 (2.8 - 3.5L for 70kg)
How many L’s of plasma in a healthy 70kg adult?
3.0L.
Capillary membrane
The membrane between Plasma and interstitial fluid. It is permeable to small charged ions, but tight enough to prevent blood proteins from leaking out of the plasma.
How many liters of TBW in a 70kg male?
42L, or 60% of kg.
How many liters of TBW in a 100kg person?
60L (60%)
How much of 42L is ICF?
28L (2/3rds)
How much of 42L is ECF?
14L
Of the 14L of ECF, how much is Interstitial fluid?
11L (3/4 - 4/5)
Of the 14L of ECF, how much is plasma?
3L or 2.8 - 3.5L(1/5 - 1/4)
What can ECF do in the event of hemorrhage?
Can transfer fluid from ISF across capillary membrane to Plasma so it can enter cardiovascular system to make up for volume loss.
How much plasma in a 100kg patient?
First step: patient has 60L of TBW.
Second step: ECF is 1/3rd of 60L, therefore there is 20L of ECF in this patient.
Third step: Plasma is 1/5 - 1/4 of ECF, therefore its 4 - 5L of plasma in a 100kg pt.
Is steady state the same as equilibrium?
No! steady state is the same usual of compounds inside and outside the cell, but they are NOT equal! Equal Na+ inside and outside the cell would be disastrous. There may be 10x more Na+ outside the cell than inside, but thats STEADY.
Na+ ICF and ECF
ECF: 140-142
ICF: 14
Ratio is 10:1 outside to in!!!
K+ role, ICF and ECF
Determines how the heart functions
ECF: 4.0!
ICF: 120
30x higher INSIDE than outside, this is why when cells die and release their K+ into the ECF, the pt becomes hyperkalemic
Ca++ ratio and role
10,000 to 1 ECF to ICF ratio! not found inside the cell. Helps turn cell on/off
Mg++ role, higher in ECF or ICF?
cofactor in intracellular reactions, thats why its found more INSIDE THE CELL (ICF) in the cytoplasm.
Cl- role, higher in ECF or ICF?
Follows sodium, it is the anion (sodium is the cation). Mostly in ECF, it is the anion of ECF!!
HCO3- (bicarb) role, higher in ECF or ICF?
Managed by kidneys, PRIMARY ECF BUFFER, therefore higher in ECF
Phosphate (HPO4=) role, higher in ECF or ICF?
Additional buffer for ICF, therefore higher in ICF. It sticks to targets to turn them on/off, changing activity levels of pathways, and also acts as an energy storage system for ATP.
What is ATP?
Adenosine Triphosphate, 1 adenosine and 3 phosphate. When phosphate is pulled of adenosine, creates energy.
Amino acids, role and higher in ECF or ICF?
Puts proteins together inside the cell, therefore ICF
Creatine, role and higher in ECF or ICF?
Much higher in ICF, mostly found in skeletal muscle as a high energy storage compound. Muscle contraction pulls phosphate off ATP. Burns quickly!
Lactate, role and higher in ECF or ICF?
Not much difference between ICF and ECF, just know it’s a byproduct of metabolism.
ATP, role and ECF or ICF?
ONLY ICF! it is not found in ECF. it is created inside the cell and burned inside the cell.
What can happen to adenosine after the triphosphate is burned?
It can leak outside the cell and increase blood flow, as it opens blood vessels.
Total mOsm/L
total compounds of everything in fluid, 300!!
Corrected osmolar activity, why is this needed separately from total osmo?
280-283. Na+ and cl- can sometimes not separate and therefore not function as independent compounds.
what is mm hg?
millimeters of mercury
Osmotic pressure at 37 degree celsius?
ECF and ICF both 5400+
Glycolipids
Sugars stuck to phospholipids (need to go back over slide 27!!!!)
Glycoproteins
Sugars stuck to proteins in cell wall
Glycocalyx
Glycolipids and glycoproteins stuck together. Immune function. When your blood sugar is elevated, you have extra sugars on the glycocalyx and make them less effective.
Proteins in cell wall can act as what?
Ion channels/pumps
Is the lipid tail charged or non-charged?
Non-charged, its FAT
What kind of bonds are the phospholipids made of?
Carbon to carbon bonds, sometimes double carbon bonds
What’s the shape and context of the cholesterol membrane??
Flat (planar) and rigid
Chemical makeup of cholesterol molecule
Only carbon single and double bonds with hydrogen molecules, with a OH head that is the only water soluble part of the compound. This is where it is exposed to water and how the body grabs it.
Characterics of the cholesterol cell wall
Rigid, hurts flexibility!
Needs cards on slide 31-32
