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32 Cards in this Set
- Front
- Back
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Water
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-Is the most vital aspect of life
*Constitutes 60% of adult body weight -Physiologically water is involved in: *medium for nutrients and waste *maintenance of large structures(EX. glycogen) *metabolic reactions *serves as a solvent *lubricant and shock absorption *aids in body temperature maintenance *maintains blood volume **water balance very important for maintenance of processes |
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Two Fluid Mediums in Body
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-Intracellular fluid (inside cell)
-Extracellular fluid (outside cell) -Both mediums composed specifically for function *any change body quickly adapts *if not consequences can be bad |
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Bodies Response to Fluid Balance
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-Coordinated response between kidneys and hypothalamus
1. Kidney responds to decrease in blood flow (hormonal response) 2. Hypothalamus signals thirst (hunger) 3. Dry mouth sensation (easily turned off) 4. Turned off by stretch receptors in stomach and blood vessels *Dehydration |
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Dehydration
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-1-2 (body weight lost %) thirst, fatigue, weakness, vague discomfort, loss of appetite
-3-4 impaired physical performance, dry mouth, reduction in urine, flushed skin, impatience, apathy -5-6 difficulty concentrating, headache, irritability, sleepiness, impaired temperature regulation, increased respiratory rate -7-10 dizziness, spastic muscles, loss of balance, delirium, exhaustion, collapse |
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Water Sources
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-Any beverage (though some are better than others)
-Foods contain water -Can be generated through metabolism |
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Water Intoxication
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-Rare
-Confusion, convulsions and death -Excessive intake -Kidney dysfunction -More common in athletes who have low sodium (hyponatremia) |
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Water Losses
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-Body must excrete 500 ml per day for waste clearance
-Adjusts to intake -water lost via: 1. Urine 2. Sweat 3. Feces 4. Breathe |
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Osmosis
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-Movement of water across a membrane to the side of high concentration
*when placed into water salts disassociate into negative and positive ions. **+ions=cations; -ions=anions *water encapsulates ions *the disassociated ions attract water and are normally called: Electrolytes *the amount of electrolytes in a solution is measured in milliequivalents -electrolytes consist of charged minerals, some acids, and proteins |
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Osmotic Pressure
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-Amount of pressure needed to prevent movement of water
*based on salts in fluid mediums |
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Major Cation Electrolytes
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-Sodium (Na+) - extracellular
-Potassium (K+) - intracellular --Na and K *always move in opposite directions *major part of membrane potentials *create action potentials |
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Proteins Contribute in Two Ways
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-Attract water
-Regulate ion passing as a membrane channel *Na/K ATPase pump -Other involved include: *chloride, phosphate, organic acids, calcium, magnesium, bicarbonate |
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Body Uses Ions to Regulate pH of Fluids
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-Prevents shifts in pH
-Deviations can have a negative effect on body function -Three systems: 1. buffers using bicarbonate and carbonic acid 2. respiration 3. kidneys -Regulation of fluids and electrolytes is an extensive process *kidneys and brain involved |
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Loss of Electrolytes
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-Sweat (Na and CL)
-Vomiting (Na) -Diarrhea (Na) -Excretion (usually due to disease or over stimulation) -Replenished with food and water as well as electrolyte drinks (gatorade) |
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Minerals
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-Not organic
-Single molecules -Two classes: *major minerals *trace minerals -Body handles minerals like vitamins to some degree -Bioavailability depends on if mineral is bound to another molecule *some plant minerals are difficult to absorb -Nutrient interactions take place like vitamins -Vary in roles in physiology |
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Sodium
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-Found primary as sodium chloride (NaCI) or more commonly called "salt"
-Functions as the chief extracellular cation -Sodium implicated in two disease states: 1. Hypertension 2. Osteoporosis |
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Sodium and Hypertension
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-Salt more potent for raising blood pressure then Na alone
-Reduction in use of salt lowers blood pressure -People at risk include: *diabetics, obese, heredity, >50 yrs, african americans, kidney disease |
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Sodium and Osteoporosis
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-Possible link
-Increased sodium intake increases Ca excretion -Research inconclusive |
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Sodium in Food
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-In most foods
-Processed foods have highest content -75% of Na in diet comes from processed foods -15% from added salt -10% from natural food |
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Sodium Deficiency
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-Hyponatremia
*confusion and disorientation common *common from vomiting, diarrhea, and excess exercise -Toxicity *may contribute to hypertension |
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Chloride
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-Major extracellular anion
-Electrolyte and acid-base -Found in most foods -Rare deficiency -Rare toxicity |
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Potassium (K)
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-Function similar to sodium
-Intracellular cation -Potassium and hypertension: *low K is diet correlates to hypertension -Food Sources: *fruits (banana), veggies, meats, grains, legumes |
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Potassium Deficiency
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-Muscle weakness, paralysis, confusion
-Most common electrolyte imbalance -Caused by: *dehydration, vomiting, steroids, diabetic acidosis, diarrhea, diuretics |
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Potassium Toxicity
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-Hard to get toxic effect
-Caused by excessive supplementation -If injected into vein can stop heart -Muscle weakness, vomiting |
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Calcium
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-Most abundant mineral in the body
-99% found in bone and teeth -Function: *main part of bone *vital functions for life -Most vital of all minerals *1% of Ca in fluid mediums very important *vital for: 1. muscle contraction 2. nerve transduction 3. hormone secretion 4. part Ca/calmodulin |
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Calcium and Bone
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-MINERALIZATION of bone occurs when Ca as well as phosphorus form crystals and bind to collagen matrix
-Crystals are called HYDROXYAPATITE |
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Calcium's Role in Disease Prevention and Obesity
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-Disease prevention:
*lowers blood pressure *diabetes *cancer *osteoporosis -Obesity *inverse relationship between Ca intake and incidence of obesity *dairy Ca seems to be the best *may be due to increased hormonal action *still more research to be done |
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Calcium Balance
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-Blood calcium changes as a result of an abnormal regulatory response
-Diet deficiency of Ca Does Not effect Blood Calcium* -Calcium rigor- excessive levels -Calcium tetany- low levels --Lack of vitamin D and abnormal regulation cause |
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Calcium Balance Tightly Regulated by Body
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-Prolonged drop in serum Ca eventually results in death
-Controlled by hormones and vitamin D -Bone is the major storage site for Ca in body -Two hormones are: 1. Parathyroid hormone- when levels are low this stimulates an increase by taking from bone 2. Calcitonin- when levels are high stimulates bone formation |
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Calcium Absorption
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-Calcium binding protein (CBP)
-Regulated by vitamin D -Increased activity in pregnant women and children (50-60%) -Adults (25%) -Binders may make Ca difficult to absorb |
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Calcium Deficiency
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-Decreased bone mineralization
-Lower peak bone mass -Development of osteoporosis |
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Calcium and Food
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-Source may effect absorption
-Phytates and oxalates binders in leafy veg. that blocks absorption of Ca -Milk best source bc of vitamin D -For the most part Ca is in a variety of foods -Vegetarians need to use strategy |
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Phosphorus-Calcium Ratio
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-Issue lies in Soda replacing milk as a beverage of choice
*soda is high in phosphoric acid |
