water and major minerals. b water is an essential nutrient. b can only last a few days without it. b...
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Water and Major MineralsWater and Major Minerals
WaterWater andand MajorMajor MineralsMinerals
Water is an essential nutrient.Water is an essential nutrient.Can only last a few days without it.Can only last a few days without it.The minerals maintain adequateThe minerals maintain adequate
distribution of water in the body.distribution of water in the body.Water is inside and outside of Water is inside and outside of
every cell in the body.every cell in the body.
Water’sWater’s functionfunction inin thethe bodybody..
Carries nutrients to and waste Carries nutrients to and waste products from the cells.products from the cells.
Serves as a solvent and takes Serves as a solvent and takes part in metabolic reactions.part in metabolic reactions.
Acts as a lubricant around Acts as a lubricant around joints.joints.
Regulates body temp and blood Regulates body temp and blood volume.volume.
Slide 4
Figure 12-4Page 402
Water Dissolves Salts and Follows Electrolytes
Na+O H
-ClNa+
-Cl
H
__
+
+
The structural arrangement of the two hydrogen atoms and one oxygenatom enables water to dissolve salts. Water’s role as a solvent is one ofits most valuable characteristics.
WaterWater homeostasishomeostasis
60 % of adult weight is water.60 % of adult weight is water.Hypothalamus regulates water Hypothalamus regulates water
intake by stimulating thirst.intake by stimulating thirst.Dehydration: deprivation or Dehydration: deprivation or
excessive loss of fluid.excessive loss of fluid.Water intoxication: kidney Water intoxication: kidney
failure.failure.
Slide 6
Table 12-1Page 397
WaterWater sourcessources..
Beverages in the diet.Beverages in the diet.Water content of food, up to Water content of food, up to
90%.90%.Metabolic water.Metabolic water.These 3 sources average 2 1/2 These 3 sources average 2 1/2
L.L.
Slide 8
Table 12-2Page 397
WaterWater losseslosses
Body must excrete 500 ml every Body must excrete 500 ml every day to discard waste products.day to discard waste products.
Water lost as vapor from lungs Water lost as vapor from lungs and sweat from skin; 1/2 of and sweat from skin; 1/2 of loss.loss.
Some water lost in feces.Some water lost in feces.Average loss is 2 1/2 L.Average loss is 2 1/2 L.
Slide 10
Table 12-3Page 398
WaterWater andand blood volumeblood volume
Water maintains blood volume.Water maintains blood volume.Kidneys regulate blood volume Kidneys regulate blood volume
by releasing or retaining water.by releasing or retaining water.Hypothalamus activates Hypothalamus activates
pituitary gland to secrete ADH pituitary gland to secrete ADH to retain water by kidneys and to retain water by kidneys and signal thirst.signal thirst.
WaterWater andand bloodblood pressurepressure
Kidneys release enzyme renin Kidneys release enzyme renin which causes kidneys to which causes kidneys to reabsorb sodium; water follows reabsorb sodium; water follows sodium.sodium.
Renin activates angiotensin Renin activates angiotensin which constricts blood vessels.which constricts blood vessels.
Angiotensin activates Angiotensin activates aldosterone which retains more aldosterone which retains more Na+ and waterNa+ and water
Water distribution in body.Water distribution in body.
2/3 inside and 1/3 outside cells.2/3 inside and 1/3 outside cells.Mineral salts dissolved in water Mineral salts dissolved in water
become cations (+) or anions (-).become cations (+) or anions (-).Electrolytes are mineral salts.Electrolytes are mineral salts.Electrolytes attract water and Electrolytes attract water and
help to maintain homeostasis.help to maintain homeostasis.
Slide 14
Figure 12-1Page 397
One Cell and Its Associated Fluids
Fluid between thecells (intercellularor interstitial)
Nucleus
Cellmembrane
Fluid within thecell (intracellular)
Blood vessel
Fluid (plasma) within the bloodvessels (intravascular)
Electrolyte distributionElectrolyte distribution
Sodium and chloride are outside Sodium and chloride are outside the cells.the cells.
Potassium, magnesium, sulfate, Potassium, magnesium, sulfate, phosphate are inside the cells.phosphate are inside the cells.
Water follows electrolytes across Water follows electrolytes across the cell membranes; osmosis.the cell membranes; osmosis.
Electrolytes must be = in charge.Electrolytes must be = in charge.
Slide 16
Table 12-4Page 402
Slide 17
Figure 12-5Page 403
Osmosis
Water can flow both waysacross the divider, but has agreater tendency to move fromside A to side B, where thereis a greater concentration ofsolute. The volume of waterbecomes greater on side B,and the concentrations onside A and B become equal.
32 Now additional solute isadded to side B. Solute cannotflow across the divider (in thecase of a cell, its membrane).23
1 With equal numbers of soluteparticles on both sides, theconcentrations are equal,and the tendency of water tomove in either direction isabout the same.
Slide 18
In-text Figure Page 403When sprinkled with salt, vegetables “sweat” because water moves
toward the higher concentration of salt outside the eggplant.
Fluid and Electrolyte Fluid and Electrolyte imbalance.imbalance.
Vomiting, diarrhea, profuse Vomiting, diarrhea, profuse sweating, burns, draining sweating, burns, draining wounds may cause imbalance.wounds may cause imbalance.
Sodium and chloride easily Sodium and chloride easily lost.lost.
Electrolytes and fluids must be Electrolytes and fluids must be replaced when imbalance replaced when imbalance occurs.occurs.
Acid-base balanceAcid-base balance
Normal pH is 7.35 to 7.45 for Normal pH is 7.35 to 7.45 for blood.blood.
Proteins are damaged beyond Proteins are damaged beyond normal range; body can’t function.normal range; body can’t function.
Buffers in blood, rate of respiration Buffers in blood, rate of respiration and regulation by kidneys maintain and regulation by kidneys maintain acid-base balance.acid-base balance.
Slide 21
Figure 12-6Page 405
The pH Scale
Basic
pH neutral
Acidic
Death
Normal and abnormalpH ranges of blood
pH’s of commonsubstances
Death
Acidosis
Normal
Alkalosis
8.00
7.45
7.35
6.8
Battery acid
Gastric juiceLemon juice
Vinegar
Concentrated lye
Household ammonia
Baking soda
Pancreatic juice
WaterBlood
MilkUrine
Coffee
Orange juice
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Major mineralsMajor minerals
Inorganic elements; can not Inorganic elements; can not be destroyed in food prep.be destroyed in food prep.
May be bound by food May be bound by food compounds or interact with compounds or interact with other minerals.other minerals.
May not be absorbed.May not be absorbed.All have upper levels of intake.All have upper levels of intake.
Sodium functionsSodium functions
Principal cation and regulator of Principal cation and regulator of volume in extracellular fluid.volume in extracellular fluid.
Essential for nerve Essential for nerve transmission, muscle transmission, muscle contraction, acid-base balance.contraction, acid-base balance.
Kidneys filter out excess.Kidneys filter out excess.
Sodium and healthSodium and health
Need a minimum of 500 mg Need a minimum of 500 mg Na+.Na+.
Salt sensitive individuals may Salt sensitive individuals may benefit from Na+ restriction.benefit from Na+ restriction.
Hyponatremia: low blood Na+.Hyponatremia: low blood Na+.Na+ toxicity: edema and Htn.Na+ toxicity: edema and Htn.Processed foods are high in Processed foods are high in
Na+.Na+.
Slide 25
Figure 12-8Page 409
What Processing Does to the Sodium and Potassium Contents of Foods
Milk (whole)
Unprocessed
Peach pie
Processed
Canned,cream corn
Instantchocolatepudding
Oat cereal
Freshpeaches
Milks
Chipped beef
Vegetables
Fresh corn
Meats
Roast beef
Fruits
Rolled oats
Grains
Sodium
Potassium
Key:
Chloride functions.Chloride functions.
Major anion in extracellular Major anion in extracellular fluid.fluid.
Part of hydrochloric acid.Part of hydrochloric acid.Maintains fluid and Maintains fluid and
electrolyte balance. electrolyte balance.
Chloride and healthChloride and health
Adequate intake for adults is Adequate intake for adults is 2300 mg/day for 19-50 year olds2300 mg/day for 19-50 year olds
Need for Cl decreases with ageNeed for Cl decreases with ageDeficiency: rareDeficiency: rareToxicity may occur due to Toxicity may occur due to
dehydration.dehydration. Processed foods are high in NaClProcessed foods are high in NaCl
Potassium functionPotassium function
Principal cation inside cells.Principal cation inside cells.High intake appears to reduce High intake appears to reduce
high blood pressure.high blood pressure.Potassium and sodium trade Potassium and sodium trade
places across cell membranes places across cell membranes during nerve transmission during nerve transmission and muscle contraction.and muscle contraction.
Potassium and healthPotassium and health
Adequate intake for adults is Adequate intake for adults is 4700 mg/day.4700 mg/day.
Best source is fresh fruits and Best source is fresh fruits and veg.veg.
K+ deficiency is most common K+ deficiency is most common electrolyte imbalance; weakness.electrolyte imbalance; weakness.
Caused by diuretics, dehydration,Caused by diuretics, dehydration,
DM acidosis, vomiting, steroids.DM acidosis, vomiting, steroids.
Slide 30
In-text Figure Page 411
Fresh foods, especially fruitsand vegetables, providepotassium in abundance.
Calcium functionCalcium function
99% is found in bones and 99% is found in bones and teeth.teeth.
Cation regulates muscle Cation regulates muscle contraction, blood clotting, contraction, blood clotting, nerve transmission, secretion nerve transmission, secretion of hormones, activation of of hormones, activation of enzymes and regulates blood enzymes and regulates blood pressure.pressure.
Calcium and healthCalcium and health
Recommendations for bone Recommendations for bone healthhealth
1000 mg for 19-50 years 1000 mg for 19-50 years oldold
1200 mg for 50 + years.1200 mg for 50 + years.Calcium taken from bones Calcium taken from bones
when blood calcium is low.when blood calcium is low.
Slide 33
Figure 12-13Page 417
Phases of Bone Development throughout Life
Bonedensity
Bone lossActive growth
Peak bone mass
years
Slide 34
Figure H12-3Page 431
Bone Losses over Time Compared
Woman B had less bonemass starting out and sosuffered ill effects frombone loss later on.
Age 30
Danger zone
Menopause
Bo
ne
mas
s
Time
Woman A entered adulthoodwith enough calcium in herbones to last a lifetime.
Age 60
Osteoporosis
Slide 35
Figure 12-11Page 415
Maintaining Blood Calcium from the Diet and from the Bones
With an adequate intake ofcalcium-rich food, bloodcalcium remains normal...
With a dietary deficiency,blood calcium still remainsnormal...
...because bones give up calcium to the blood. The result is weak, osteoporotic bones.
...and bones deposit calcium. The result is strong, dense bones.
Calcium sourcesCalcium sources
Milk products, tofu, sardines Milk products, tofu, sardines with bones, bok choy, black with bones, bok choy, black strap molasses, fortified strap molasses, fortified orange juice, corn tortillas, orange juice, corn tortillas, broccoli broccoli
Slide 37
In-text Figure Page 417
Milk and milk products are rightlyfamous for their calcium contents.
Slide 38
In-text Figure Page 417
Bioavailability of Calcium from Selected Foods
Cauliflower, watercress,brussels sprouts, rutabaga,kale, mustard greens, bokchoy, broccoli, turnip greens
>50%absorbed
>30%absorbed
>20%absorbed
>5%absorbed
Milk, calcium-fortified soymilk, calcium-set tofu,cheese, yogurt, calcium-fortifiedfoods and beverages
Almonds, sesame seeds,pinto beans, sweet potatoes
Spinach, rhubarb, Swisschard
_
_
_
_
Phosphorus functionPhosphorus function
Part of bones and teethPart of bones and teeth Found in all body cells; used as a Found in all body cells; used as a
bufferbuffer Part of DNA and RNAPart of DNA and RNA Part of ATP, the energy moleculePart of ATP, the energy molecule Activates enzymes and B vitaminsActivates enzymes and B vitamins Part of phospholipids, part of cell Part of phospholipids, part of cell
membranes, transports other lipidsmembranes, transports other lipids
Phosphorus and healthPhosphorus and health
RDA: 700 mg per day for adultsRDA: 700 mg per day for adults Sources: meats, milk products, Sources: meats, milk products,
legumes, soda with phosphoric acidlegumes, soda with phosphoric acid Dietary deficiency unknownDietary deficiency unknown High phosphorus, low calcium blood High phosphorus, low calcium blood
levels will lead to bone loss in levels will lead to bone loss in people with kidney failure.people with kidney failure.
Magnesium functionMagnesium function
Over half of magnesium is found in Over half of magnesium is found in the bones and dental enamelthe bones and dental enamel
Found in muscles and soft tissueFound in muscles and soft tissue Necessary for body’s production of Necessary for body’s production of
protein and for energy metabolismprotein and for energy metabolism Part of many enzymesPart of many enzymes Inhibits muscle contraction and Inhibits muscle contraction and
blood clotting; calcium promotes blood clotting; calcium promotes thesethese
Magnesium and healthMagnesium and health
RDA: 400 mg per day for men RDA: 400 mg per day for men RDA: 310 mg per day for womenRDA: 310 mg per day for women Sources: legumes, seeds, nuts, leafy Sources: legumes, seeds, nuts, leafy
green vegetablesgreen vegetables Deficiency: tetany; impaired central Deficiency: tetany; impaired central
nervous system function; constricted nervous system function; constricted circulatory system, may cause Htncirculatory system, may cause Htn
Toxicity: rare; fatal; from supplements Toxicity: rare; fatal; from supplements
Sulfur functionSulfur function
Found in essential nutrients such Found in essential nutrients such as vitamins and amino acidsas vitamins and amino acids
Sulfur bonds shape protein Sulfur bonds shape protein molecules and provide stability to molecules and provide stability to the protein structurethe protein structure
Skin, hair, nails contain sulfur Skin, hair, nails contain sulfur containing protein moleculescontaining protein molecules
Sulfur and healthSulfur and health
No RDA for sulfurNo RDA for sulfur No known deficiency; diet would No known deficiency; diet would
have to be deficient in protein rich have to be deficient in protein rich foodsfoods
Sources: meats, eggs, milk, Sources: meats, eggs, milk, legumes, nutslegumes, nuts
Slide 45
Click to view animation.
Bacteriophage studies
Animation
Slide 46
Figure 12-2Page 400
A Nephron, One of the Kidney’s Many Functioning Units
Renal artery
Kidney
Pelvis
Ureter
Bladder
Kidney, sectionedto show locationof nephrons
A nephron (a working unit of the kidney).Each kidney contains over one million nephrons.
The tubule passes wastematerials on to the bladder.
Renal vein
Blood flows into the glomerulus,and some of its fluid, withdissolved substances, isabsorbed into the tubule.
Then the fluid and substancesneeded by the body are returnedto the blood in vessels alongsidethe tubule.
To the bladder
Capillariesof glomerulus
Glomerulus
To the body
Blood vessel
Tubule
3
2
1
The cleansing of blood in the nephron is roughly analogousto the way you might clean your car. First you remove all yourpossessions and trash so that the car can be vacuumed.(1)Then you put back in the car what you want to keep(2) andthrow away the trash. (3)
3
2
1
Slide 47
Figure 12-3Page 401
How the Body Regulates Blood Volume
Aldosterone
Angiotensin causesthe blood vesselsto constrict, raisingpressure.
The hypothalamus respondsto high salt concentrationsin the blood by stimulating
the pituitary gland.
Renin initiates the activation of the protein angio-
tensinogen to angiotensin.
Angiotensin signalsthe adrenal gland to secrete aldo-sterone.
BrainKidneys
Aldosterone and ADH signal the kidneys to retain sodium and water,respectively, thus increasing blood volume.
The kidneys respond toreduced blood flow byreleasing the enzyme
renin.
The pituitary glandreleases antidiuretic
hormone (ADH).
Renin
Angiotensin
ADH
Slide 48
In-text Figure Page 403When immersed in water, raisins get plump because water moves
toward the higher concentration of sugar inside the raisins.
Slide 49
In-text Figure Page 404
Physically active people must rememberto replace their body fluids.
Slide 50
Figure 12-7Page 406
Minerals in a 60-kilogram (132-pound) Human Body
TRACE MINERALSThere are more than a dozen trace minerals,although only six are shown here.
Amount (g)
MAJOR MINERALSThe major minerals are those present in amountslarger than 5 g (a teaspoon). A pound is about454 g; thus only calcium and phosphorus appearin amounts larger than a pound.
Slide 51
In-text Figure Page 408
Fresh herbs add flavor to a recipewithout adding salt.
Slide 52
Figure 12-9Page 412
Potassium in Selected Foods
Key:
Fruits
Milk and milk products
Legumes, nuts, seeds
Meats
Best sources per kcalorie
Breads and cereals
Vegetables
POTASSIUMFresh fruits (purple), vegetables(green), legumes (brown), andmeats (red) contribute potassiumto the diet.
Food Serving size (kcalories)
Milligrams
The AI for potassium is 4700 mgper day.
0 200 400 600 800
Slide 53
Figure 12-10Page 414
Calcium Balance
Parathormonestimulates theactivation ofvitamin D.
Rising blood calciumsignals the thyroidgland to secretecalcitonin.
Calcitonin limitscalcium absorptionin the intestines.
Calcitonininhibits theactivationof vitamin D.
Parathyroid(embeddedin the thyroid)
Falling blood calciumsignals the parathyroidglands to secreteparathormone.
Vitamin D
Vitamin DActivation
Vitamin Denhances calciumabsorption inthe intestines.
All these actions raise bloodcalcium levels, which inhibitsparathormone secretion.
All these actions lower bloodcalcium levels, which inhibitscalcitonin secretion.
Vitamin D andparathormonestimulate calciumreabsorptionin the kidneys.
Vitamin D andparathormonestimulateosteoclast cells tobreak down bone,releasing calciuminto the blood.
Calcitoninprevents calciumreabsorptionin the kidneys.
Calcitonin inhibitsosteoclast cellsfrom breakingdown bone,preventing therelease of calcium.
Intestines
Kidneys
Bones
CalcitoninParathormone
Thyroid
Slide 54
Figure 12-12Page 416
Calcium in Selected Foods
Label
Key:
Fruits
Milk and milk products
Legumes, nuts, seeds
Meats
Best sources per kcalorie
Breads and cereals
Vegetables
CALCIUMAs in the riboflavin figure, milk and milk products (white)dominate the calcium figure. Most people need at least threeselections from the milk group to meet recommendations.a Values based on products containing added calcium salts;the calcium in 1⁄2 c soybeans is about 1⁄3 as much as in1⁄2 c tofu. b If bones are discarded, calcium declines dramatically.
Food Serving size (kcalories)Milligrams
AI formen
19–50
AI formen51+
AI forwomen19–50
AI forwomen
51+
Slide 55
Figure 12-14Page 419
Phosphorus in Selected Foods
Key:
Fruits
Milk and milk products
Legumes, nuts, seeds
Meats
Best sources per kcalorie
Breads and cereals
Vegetables
PHOSPHORUSProtein-rich sources, such asmilk (white), meats (red), andlegumes (brown), provideabundant phosphorus as well.
RDAfor
adults
Food Serving size (kcalories)Milligrams
Slide 56
Figure 12-15Page 421
Magnesium in Selected Foods
Key:
Fruits
Milk and milk products
Legumes, nuts, seeds
Meats
Best sources per kcalorie
Breads and cereals
Vegetables
MAGNESIUMLegumes (brown) are a richsource of magnesium.
RDA forwomen19-31
RDA formen19-30
Food Serving size (kcalories)Milligrams
Slide 57
In-text Figure Page 428
Osteoporosis andCalcium
Slide 58
Figure H12-1Page 429
Healthy and Osteoporotic Trabecular Bones
Electron micrograph of trabecular boneaffected by osteoporosis.
Electron micrograph of healthytrabecular bone.
Slide 59
Figure H12-2Page 430
Loss of Height in a Woman Caused by Osteoporosis
80 years old
6 inches lost
50 years old
Slide 60
Table H12-1Page 430
Slide 61
Table H12-2Page 430
Slide 62
In-text Figure Page 432
Strength training helps tobuild strong bones.