A&P II Fluid & Electrolytes
name the two most common positive electrolytes which are found both inside and outside of cells?
Calcium and Magnesium
what is an electrolyte?
a salt that dissolves in water to form charged ions
when do the symptoms of dehydration come about?
after the loss of about 2 liters of water
what's thirst?
an awareness of the need for water created by the hypothalamus
what is the most common negative ion outside the cell?
chlorine
name the most common negative electrolytes
chlorine, PO4-, SO4-, & CO4- aka phosphates, carbonates, and sulfates
what will excess H+ in the urine cause?
excess K+ to be retained
what will cause excess K+ to be retained?
excess of H+ in urine
name 4 symptoms of dehydration
headache, fatigue/weakness, confusion, dry membranes
what is the term for under volume blood?
hypovolemic
what do kidneys do to fluid balance?
kidneys selectively secrete excess electrolytes to maintain correct ratio of water & electrolytes in intracellular fluid (63%), blood plasma (8-9%), & interstitial fluid (28%)
name some inputs of water into the body
liquids, food, metabolic water (from the break-down of food molecules that release water)
what does the loss of up to 16lbs of water (so like 4-8 liters) result in?
loss of temperature control, loss of muscle control& cramps, very confused leading to coma which can lead to shock
what is the minimum amount of urine you have to make per day called?
obligate volume
name the most common positive ion (electrolyte) inside the cell
potassium
name some ways body water is lost
respiration, evaporation, fecal material, urination
what is pH maintained by?
selective secretion or retention of hydrogen ions
name the most common positive ion (electrolyte) outside the cell
sodium
name 4 common electrolytes that are positive
sodium, potassium, calcium, and magnesium
what are 4 important functions of water?
temperature regulation, chemical reactions, as a solvent, lubricant/protectant
when/why does the awareness of thirst come?
when you've lost about a half a liter of water or hypothalamus checks sodium content of blood and finds sodium content too high... this triggers the hypothalamus to create the feeling of thirst
how much water is recommended to drink (per day)?
2,000-3,500 mL + what you need if it's extra hot, or you exercise, or your pregnant
how much water in the body is IN BETWEEN cells?
28%
what percentage of normal diet is water?
30%
what is the minimum amount of urine you have to make per day?
400 mL
how much water is normally lost by respiration?
500 mL of water per day
how much water is normally lost by evaporation?
500mL per day
how much body weight is water?
60%
how much of total body water is IN cells?
63%
how much water in the body is in blood?
8-9%
name the 3 most common negative electrolytes IN the cells
PO4- SO4- CO4-