Exam 4 - electrolytes

what is the fluid compartment which holds about 65% of fluid

intracellular fluid

volume excess refers to both __ and __ being retained and the ECF remains isotonic

sodium, water

hypotonic hydration means there is more __ being retained than ___ and the ECF become ___

water, sodium, hypotonic

what are the 6 most important electrolytes

sodium, potassium, chloride, bicarb, calcium, and phosphate

what is the principal cation in the ECF and accounts for 90-95% of osmolarity in the ECF

sodium

increased sodium levels can result in hypernatremia where there is water loss from the blood. An imbalance between ADH and aldosterone can result where ADH levels will ___ and aldosterone levels will ___

decrease, increase

what is the most abundant cation of the ICF

potassium

what is a major determinant of the resting membrane potential

ration of EC to IC potassium

what percent of potassium in glomerular filtrate is reabsorbed by the PCT

90

what is the most dangerous type of electrolyte imbalances

potassium

absolute hypokalemia results from things such as sweating, chronic vomiting, excessive laxative use, aldosterone hypersecretion, or metabolic alkalosis. What causes relative hypokalemia

insulin-dependent diabetic patient

what is the most abundant anion of the ECF

chloride

do chloride ions act in a passive or active manner

passive

high chloride levels in sweat can be used to diagnose what disease

cystic fibrosis

what is the second most abundant anion in the blood

bicarb

what is the primary function of bicarb

maintain acid-base balance

what percentage of co2 is converted into bicarb

70

what is the equation for bicarb reactions

co2+h2o <-> H2CO3 <-> HCO3- + H+

what enzyme converts co2 into bicarb in the cytoplasm of RBCs

carbonic anhydrase

what is the normal pH of blood

7.35-7.45

what is the physiological buffer system

controls output of acids, bases, or CO2

what system buffers the greatest quantity of acid or base

urinary

which system can buffer acid or bases within minutes but cannot altar pH as much as the urinary system

respiratory

what substance is used for buffering in the blood and cells

proteins

how does hemoglobin act as a buffer

it binds hydrogen

phosphate buffer plays a significant role in the buffering of ___

urine

what is the primary buffering system of the interstitial fluid surrounding the cells in tissues throughout the body

bicarb-carbonic acid buffer

carbonic acid is a weak ___ and bicarb is a weak ___

acid, base

higher concentration of carbon from hypoventilation means pH goes ____

down