Chapter 12: Body Water and Electrolyte Homeostasis

Question 1

Whole blood

Answer 1

Plasma (55%), buffy coat (<1%), erythrocytes (45%)

Question 2

Plasma

Answer 2

Composed of water, ions, and macromolecules such as fibrinogen and other proteins

Question 3

Serum

Answer 3

Liquid part if blood remaining after a clot has formed; lacks the protein fibrinogen and other clotting factors

Question 4

Anion gap

Answer 4

Difference between the sum of measured cations and the sum of measured anions

Question 5

Osmolarity

Answer 5

Concentration per volume of solution, where 1 osmolar solution contains 1 osmol/L of solution

Question 6

Osmolality

Answer 6

Solution concentrations expressed on a weight factor are temperature independent; expressed as osmol/kg; used to identify the number of moles of a particle per kilogram of water, not the kind of particle

Question 7

Osmolality formula

Answer 7

mOSm/kg = 2(Na+ mmol/L) + (glucose mmol/L / 18) + (Urea N mmol/L / 2.8)

Question 8

Osmol gap

Answer 8

Difference between the measured and calculated osmolality; measured Osm/kg - calculated Osm/kg

Question 9

Colloid oncotic pressure (COP)

Answer 9

Pressure created in a solution by the presence of large proteins called colloids

Question 10

Brain (B)-type natriuretic peptide (BNP)

Answer 10

Increases NaCl and H2O reabsorption; released in response to intravascular volume expansion and tends to reduce blood pressure and plasma volume