2. Chapter 1 DSA Flashcards
What is the equation for molarity?
amount of substance over its molecular weight.
1g/L / 180g/mol = 5.6mmol/L
How do you express concentration of ions?
in milliequivalents per liter (mEq/L)
Osmotic pressure (Pi) is calculated using vant hoffs law. pi= nCRT. What does nCRT stand for?
n is number particles
C is total solute concentration
RT is gas constant and temp
if n in the vant hoffs equation is equal to 1, the molecule does not dissociate in water. What if n is greater than 1?
They do dissociate in water
Osmolarity is the number of solute partiles per 1l of solvent while osmolality is?
the number of solute particles in 1kg of solvent
A hypertonic causes a cell to shrink, a isotonic changes nothing and a hypotonic solution causes what to the cell?
Hypotonic causes it to swell
What is defined as the weight of a volume of solution divided by the weight of an equal volume of distilled water?
specific gravity
How would once calculate total body water, ICF and ECF (intra/extracellular fluid)?
What would cause a person to have a lower total body water?
TBW (total body water) = 0.6 x (body weight)
ICF = 0.4 x body weight
ECF= 0.2 x body weight
If there is more adipose tissue, the TBW will be less
What can the ECF be further divided into?
1/4 plasma and 3/4 interstitial fluid
What is the calculation for plasma osmolality?
2(Na) + BUN/2.8 + glucose/18
In the ECF, the main cation is Na+ while the main anions are Cl- and HCO3-. What cation and anion are most prevelent in the ICF?
K+ is most predominant cation whic oragnic molecules and negatively charges groups on proteins are the major anions
What is the equation for the filtration rate of fluid across a capillary wall?
Kf(Pc-Pi) - (reflection coefficient sigma)(pi c - pi i)
What are the usual net forces of each of the starling forces?
usually Pc, Pi, and Pi i are usually bringing fluid outside of the capillary while Pi c, then oncotic pressure of the capillary will bring fluid into the capillary
