Exam 1: Ions/Electrolytes Flashcards
Intracellular sodium concentration
1/10th of plasma sodium concentration; 14
Plasma sodium concentration
140-142
How to determine overall osmolarity
sodium x 2
What is sodium used to determine?
Sodium osmolarity
Blood plasma potassium concentration
4
Intracellular potassium
30x higher than outside cells (120-140)
What do you need to know about calcium?
There is hardly any calcium floating on the inside of the cell b/c it’s used as a signal to turn itself on
What do you need to know about magnesium?
Magnesium is higher inside the cells than outside of the cells b/c it’s used as a cofactor with lots of reactions inside of the cell
What do you need to know about chloride?
Similar to sodium; more outside of the cell than inside, primary ECF anion
What does bicarb do and where is it managed?
Bicarb is the primary ECF buffer and is typically managed by the kidney; higher concentration outside of cells than inside
Why is phosphate important?
ICF buffer; higher inside of cells than outside of cells
Amino acid concentrations are higher in the _____
inside of the cell; amino acids are needed to proteins together inside of the cells
Creatine is used for what?
High energy storage compound; used prior to ATP for energy when skeletal muscles contract
What is lactate?
Metabolic byproduct inside of the cell; higher concentration inside the cell than outside
Why is ATP not found outside of cells?
It is so valuable and must remain in the cells for energy usage
Why is glucose not found inside cells?
Glucose is delivered to cells, not produced within them
What is the primary cation?
Sodium
What is the function of potassium?
Potassium determines how the heart is going to function
What is the ratio of calcium inside the cell vs outside of the cell?
10,000:1 - more outside of the cell vs inside
What is magnesium used for?
To settle the heart down with chemical reactions
What is the primary anion?
Chloride
Are there more proteins inside or outside of the cell?
Inside because that is where they are produced
What is urea?
Byproduct of metabolism
What is total osmolarity?
How many dissolved compounds are in the total fluid sample
When you measure and add up all of the numbers it is close to 300
Is the biological osmolarity greater than or less than the predicted osmolarity?
Less than b/c there are some ions that might join together and not want to dissociate as easily as predicted
What is the corrected osmolarity?
280-283
What is total osmotic pressure?
5,000+ mmHg; the pressure difference needed to prevent the flow of solvents across a semipermeable membrane = relates to the amount of “stuff” dissolved in solution
