Chapter 22 Flashcards
what type of fluid accounts for 2/3-3/4 of all body fluids?
intercellular fluid (cytosol)
sodium charge, location, function
most abundant cation in extracellular fluid
maintains osmotic balance, body fluid volume, nn impulse conduction, pH
potassium charge, location, function
most abundant cation in intracellular fluid
determines excitability of neurons and muscle cells
calcium charge and function
cation
required for bone formation, mm contraction, NT release, blood clotting
magnesium charge and function
cation
necessary for mm contraction and action of some enzymes
bicarbonate charge and function
anion
pH
chloride charge, location, and function
most abundant anion in extracellular fluids
part of HCl of stomach, regulates fluid balance, pH
phosphate charge, location, and function
anion
in plasma membranes, nucleic acids, and ATP
essential in carbohydrate metabolism, bone formation, and pH
proteins charge and location
most abundant anions in intracellular fluids
also abundant in blood
NOT IF since usually cannot cross capillary wall
normal pH range for body
7.35-7.45
3 systems for pH regulation
- buffer systems (bicarbonate, phosphate, proteins)
- respiration
- kidney function (can create bicarbonate)
acidosis vs alkalosis
acidosis pH below 7.35 - depresses NS - from decreased CO2 release, kidney disease, exercise (ketoacidosis)
alkalosis pH above 7.45 - excites NS - hyperventilation, vomiting
what is the control center for thirst?
hypothalamus - works with Na+ sensing osmoreceptors
4 hormones in feedback loops for fluid regulation
- aldosterone (to raise BP)
- ADH (to raise BP)
- angiotensin II (to raise BP)
- atrial natriuretic peptide (to lower BP)
Aldosterone function, release
adrenal steroid released indirectly to raise BP by ATII
alters Na/K handling in kidney (can also work to lower K concentrations this way)
ADH function, release
synthesized by hypothalamus, released by posterior pituitary
stimulated release with increased blood osmolarity sensed by osmoreceptors
causes kidneys to increase H2O reabsorption
diabetes insipidus is when this is low
Angiotensin II function, release
to raise BP
sensors/control center in juxtaglomerular apparatus
cells here secrete renin in response to low BP which activates ATII
works to increase BP by constricting arterioles and stimulating thirst/ADH/aldosterone release
renin
enzyme for ATII production from inactive precursors
synthesized in JG apparatus when BP is low
atrial natriuretic peptide location and function
works to decrease BP
secreted by atrial myocardial cells
causes kidneys to secrete Na and H2O
what does lack of plasma proteins result in
loss of osmotic pressure causing edema
what causes edema?
anything that increases hydrostatic (fluid) pressure or decreases osmotic pressure
both end up increasing filtration into IF
lymph may not be able to catch up or is diseased itself causing the backup
effusion
accumulation of fluid in cavity or space resulting from excess filtration
lactated ringer solution containments and function
Na, K, Ca, Cl, lactate
lactate works to metabolize to buffer bicarbonate
used in cases of burns, correcting fluid loss, or administering medications
25% serum albumin containments and function
has albumin concentration 5x higher than normal
works to pull fluid from IF spaces
used when proteins are low or for correcting edema
