What is the small cone-shaped structure that regulates homeostasis, thirst, hunger, body temperature, water balance and blood pressure?
An adrenocortical insufficiency that results in low levels of adrenal corticosteroid hormones, including aldosterone and cortisol.
In what disease do patients display hyperkalemia and hyponatremia due to aldosterone deficency?
This syndrome is caused by an increased production of adrenocorticotropic hormone (ACTH) and characterized by obesity and week muscles.
A property of a solution that is influenced by size and shape of the molecules, but not the individual composition.
What are some colligative properties?
Average water content is ______ of total body weigt.
Water content declines in:
Why do women have a lower average water content than men?
higher fat content
all of the following are functions of what?
-transport nutrients to cells
-determine cell volume
-remove waste products by way of urine
-act as body coolant by way of sweating
Intracellular fluid (ICF) account for how much of total body water?
extracellular fluid (ECF) accounts for how much of total body water?
how is the interior of each cell separated from the ECF?
by the semi permeable membrane
how is extracellular fluid subdivided?
-intravascular cellular fluid (plasma)
-interstitial cell fluid
what ECF contains 93% water and 7% lipids and proteins?
intravascular cellular fluid
what ECF surrounds the cells in the tissues?
Interstitial cell fluid
This type of movement requires ATP, solute mover from an area of lower concentration to an area of higher concentration.
Passive transport of solutes from an area of higher concentration to an area of lower concentration that eventually results in an equal distribution of solutes within the two areas.
Passive movement of fluid across a membrane from an area of lower solute concentration and comparatively more fluid into an area of higher solute concentration and comparatively less fluid. when does it stop?
Stops when enough fluids move through the membrane to equalize the solute concentrations in both sides of the membrane.
what is the average glomerular filtration rate?
it leads to the production of how much urine?
-125ml of blood every minute or about 180L/day.
-1-2 L/day of urine
if the body loses even _____ of its fluid the kidneys reabsorb more water than solute.
What does ATP stand for?
Where is ADH produced?
where is ADH stored and released?
The pituitary gland
ADH regulates the body's reabsorption of what?
what is the process that the renin-angiotensin-aldestorone system uses to regulate the reabsorption of Na and water?
- Juxtaglomerular cells secrete renin that leads to production of Angiotensin II a powerful vasoconstrictor
-angiotensin II stimulates aldosterone which raises blood pressure
-Aldosterone regulates reabsorption of Na and H20 within the nephron
This is produced as a result of renin-angiotensin mechanism and regulates the absorption of H20 and Na.
What is the cardiac hormone released when atrial pressure increases?
Atrial natriuretic peptide
what are the four ways atrial natriuretic peptide decreases ADH?
-Decreases blood pressure and reduces intravascular blood volume
-supresses renin levels
-decreases ADH release
Physical property of a solution, which is based on the concentration of solutes, expressed as millimoles per kilograms of solvent.
What are the two ways to measure osmolality in the laboratory?
Freezing point depression
vapor pressure decrease
what are the two ways the body corrects increased osmolality?
sensation of thirst
What is another name for ADH?
Disorder characterized by a deficiency of ADH that results in hypernatremia and dehydration.
Normal plasma osmolality
275-295 mOsm/kg of water
Sodium and it's associated anions account for approx ______ of osmotic activity in plasma.
How are osmolality regulation and volume regulation related?
osmolality is regulated by a change in water balance
volume is regulated by changes in sodium balance
how does excess water intake affect osmolaity and ADH?
lower plasma osmolality
supressed ADH and suppressed sensation of thirst
what is the clinical significance of excess water intake?
what are the effects of water deficit on osmolality and ADH?
increased plasma osmolality
ADH secretion and thirst sensation activation
what is the clinical significance of water deficit
why is plasma not recommended for measuring osmolality?
what is urine osmolality used to measure?
to measure the ability of the kidneys to concentrate ions
Serum osmolality is used as a comparison for what?
What is used to standardize osmometers (QC)?
sodium chloride reference solution
true or false
freezing point is a colligative property
what is the formula for calculated osmo?
The difference between the measured and calculated osmolality is called what?
Ions capable of electrical charge are what?
positively charged ions
negatively charged ions
Elecrolytes differ in concentration but totals balance to achieve a neutral electrical charge.
what are some extracellular ions?
what are some intracellular ions?
this is the principle extracellular cation that accounts for 90% of all extracellualr cations.
what is the primary function of Na
what percent of filtered sodium is reabsorbed in the PCT?
what is the recommended daily consumption of salt?
6-7.5g salt/Day or 2,400-4,500mg Na/day
What is the renal threshold of Na?
what is the hormone which regulates renal reabsorption of sodium?
This disorder is characterized by a hypersecretion of aldosterone.
what are the three important processes of regulating Na?
intake of water in response to thirst
excretion of water
blood volume status
Na reference ranges for