Body Fluid Compartments Flashcards
List proportions of fluids in body compartments
2/3 in intracellular fluid
1/3 extracellular fluid
- 80% interstitial space
- 20 % plasma
List the 3 body compartments for fluid storage
1 intracellular space
2 interstitial space
3 plasma
Which 2 barriers separate body fluid compartments
1 plasma membrane - cell and interstitial space
2 endothelial- interstitial space and plasma
What is fluid balance
- state where all compartments have fluids and salts in correct proportions
What is an electrolyte , how it’s formed and function
-inorganic substances that are formed when their ions dissolve and dissociate in fluids
1 Maintain acid-base balance
2 cofactors
3 control osmosis between compartments
4 set up membrane potentials and play a part in nerve impulses propagation
4 ways in which fluids are exchanged between compartments
1 osmosis
2 diffusion
3 absorption
4 filtration
Diff between dilute and concentrated urine from kidneys
-dilute urine has more water
Ways in which the body can gain water and the amounts
1 from food and ingesting liquid ( 2300ml / day )
2 metabolic reactions which release water ( 200ml / day )
Ways in which the body can lose water and the amounts per day
1 kidneys ( 1500 mL/ day )
2 egestion ( 100
3 evaporation from skin ( 600
4 exhalation from lungs ( 300
What is dehydration
-when water loss is greater than water gain
Describe mechanisms for water gain
- if dehydrated
1 deceased saliva flow leads to dry mouth and pharynx - increased blood osmolality wc stimulate osmoreceptors in hypothalamus
-decreased blood volume , decreased blood pressure , increased renin release by juxta glomerular cells of kidney , increased angiotensin 2 formation
2 all stimulate hypothalamus thirst center
3 increased thirst
4 increased water intake
5 water levels back to normal and stimuli stops
What does extent of salt and water loss determine
1 body fluid volume
2 body fluid osmolality
3 hormones which regulate renal absorption of Na and Cl and what they do
1 angiotensin 2 and aldosterone- promote urinary reabsortion of salts and water when dehydrated
2 ANP - atrial natriuietic peptide wc promote natriuresis ( excretion salts in water )
3 ADH ( major ) vasopressin or antidiuretic hormone - made by hypothalamus stop excess release of water and salt through urine
Effects of increased interstitial and intracellular osmolality
And the major cause
- water moves out of cell into interstitial space and cel shrinks m
- water moves into cells from interstitial space and cell swells
/changes in Na+ concentration
What is water intoxication
-rate of water intake greater than what the body can expel
What does excessive water loss coupled with intake of plain water lead to
/excessive bleeding , sweating and blood loss decrease salt conc ( Na+ )in plasma and interstitial fluid ( hyponatremia )
- intake of plain water reduces osmolality of plasma and interstitial space
- water moves into cells , swelling ( water intoxicated cells )
- convulsions , coma , death
Purpose of high conc of protein anions in plasma
/responsible for blood colloid osmotic pressure
Diff of intracellular and extracellular fluid compartments
- abundant in K ions and phosphate anions
- abundant in Na and Cl ions
Sodium location and function
- ecm
- most abundant cation ( 90% )
- maintains compartment osmolality
- transmission of impulses
Chloride location and Function
Why does it move easily between compartments
-ecm
/most abundant anion
-forming gastric acid
-balances anion conc between compartments ( RBC chloride shift )
Most cells have chloride channels and transports
Potassium location and function
- intracellular
- sets up resting cell potential
- regulate pH
- maintain intracellular fluid volume
Location and function of bi carbonate , where high and low and why
- ecm
- 2nd most prevalent
- higher in systematic capillaries due to CO2 binding with water to form it
- low In pulmonary capillaries as CO2 is released
- buffer in blood
- transport of CO2
Calcium location and function
- most abundant mineral in body found in bone ( 98% )
- mainly ecm cation
- aids in neurotransmissions , bone formation and muscle contraction
Phosphate anions location and function
- intracellular and in bone
- bone and teeth formation
- buffer in urine and fluids
Magnesium location and function
- 54% in bone and teeth
- 45% in intra and 1% ecm
- cofactors , maintain normal muscle functioning
Describe chloride shift
- RBC exchange anions using band 3 protein
- increases in intracellular H2CO3 ( due to CO2 absorption )leads to Cl- intake and bicarbonate releases
- at pulmonary capillaries CO2 released as well as H+ ions to shift equation to form CO2 from bicarbonate and decrease in intracellular bicarbonate leads to increase of Cl
-allow plasma to be storage site for bicarbonate without changing electrical charge of plasma or RBC
