DIGESTION AND NUTRITION

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CHAPTER 38

• DIGESTION AND NUTRITION

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SECTION 38.1FUNCTIONS OF THE DIGESTIVE SYSTEM

• THE DIGESTIVE SYSTEM PERFORMS SEVERAL FUNCTIONS
  IN THE PREPARATION OF FOOD FOR CELLULAR
  UTILIZATION (USE)
• 1. INGESTS FOOD (INGESTION)
• 2. DIGESTS FOOD (DIGESTION)
• 3. PUSHES FOOD ALONG DIGESTIVE
• TRACT (PERISTALSIS)
• 4. ABSORBS DIGESTED FOOD INTO
• BLOOD STREAM (ABSORPTION)
• 5. ELIMINATES UNDIGESTED
• MATERIAL FROM BODY (EGESTION)

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PARTS OF THE DIGESTIVE SYSTEM

• DIAGRAM OF THE HUMAN DIGESTIVE SYSTEM
• gtgtHANDOUT / LABEL PARTS
• gtgtTEST OVER DIAGRAM

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PROCESS OF DIGESTION

• FOOD IS DISASSEMBLED INTO ITS COMPONENT MOLECULES
  SO THE BODY CAN HAVE A SUPPLY OF RESOURCES FOR
• 1. BUILDING NEW CELLS
• 2. PROVIDING ENERGY FOR CELL
• ACTIVITIES
• 3. MAKING CHEMICALS FOR CELL
• PROCESSES
• ENTIRE PROCESS TAKES BETWEEN 24-33 HOURS

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THE MOUTH

• FIRST STOP IN THE DIGESTIVE DISASSEMBLY LINE IS
  THE MOUTH
• FOOD BITTEN OFF OR PLACED IN MOUTH AND CHEWED FOR
  10-20 SECONDS
• TONGUE MOVES FOOD AROUND AND PLACES IT BETWEEN
  YOUR TEETH FOR CHEWING

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• CHEWING IS A PART OF MECHANICAL DIGESTION THE
  PHYSICAL PROCESS OF BREAKING FOOD INTO SMALLER
  PIECES
• MECHANICAL DIGESTION INCREASES THE SURFACE AREA
  OF FOOD PARTICLES TO PREPARE THEM FOR CHEMICAL
  DIGESTION
• CHEMICAL DIGESTION THE PROCESS OF STRUCTURALLY
  CHANGING FOOD MOLECULES THROUGH THE ACTION OF
  ENZYMES

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ENZYMES

• DIGESTIVE ENZYMES ARE CHEMICALS PRODUCED BY
  GLANDS (GROUPS OF SPECIALIZED CELLS) THAT BREAK
  THE FOOD MOLECULES APART INTO SIMPLER MOLECULES
• TABLE 38.1 DIGESTIVE ENZYMES

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• TABLE 38.1 DIGESTIVE ENZYMES

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• CHEMICAL DIGESTION BEGINS IN MOUTH
• gtgtSALIVARY GLANDS IN MOUTH
• SECRETE SALIVA
• gtgtSALIVA IS A SOLUTION OF WATER,
• MUCOUS AND DIGESTIVE ENZYME
• CALLED AMYLASE
• gtgtAMYLASE BREAKS DOWN STARCH
• INTO SMALLER SUGAR MOLECULES
• CALLED DISACCHARIDES
• gtgtWHEN FOOD IS SWALLOWED,
• AMYLASE IS ALSO SWALLOWED AND
• CONTINUES TO BREAK DOWN
• STARCHES IN STOMACH (COMPLETE
• DIGESTION OF STARCHES TAKES
• ABOUT 30 MIN.)

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SWALLOWING FOOD

• ONCE FOOD IS THOROUGHLY CHEWED, TONGUE SHAPES IT
  INTO A BALL CALLED A BOLUS
• BOLUS IS PUSHED TO BACK OF MOUTH BY TONGUE TO BE
  SWALLOWED
• SWALLOWING FORCES BOLUS INTO ESOPHAGUS
• ESOPHAGUS IS A MUSCULAR TUBE THAT CONNECTS MOUTH
  TO STOMACH

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• SWALLOWING TAKES ABOUT 5-8 SECONDS
• BOLUS PUSHED DOWNWARD BY A SERIES OF INVOLUNTARY
  MUSCLE CONTRACTIONS (ALONG THE ESOPHAGUS) CALLED
  PERISTALSIS
• PERISTALSIS OCCURS ALONG THE MUSCULAR WALLS OF
  THE ENTIRE DIGESTIVE TRACT
• FLAP OF SKIN, CALLED EPIGLOTTIS, COVERS OPENING
  TO WINDPIPE TO PREVENT BOLUS FROM ENTERING LUNGS
• gtgtTEMPORARILY STOPS BREATHING
• gtgtAFTER BOLUS PASSES INTO
• ESOPHAGUS, EPIGLOTTIS OPENS

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• IF BOLUS ENTERS EPIGLOTTIS, A REFLEX OF CHOKING
  AND COUGHING OCCURS TO FORCE BOLUS OUT OF
  WINDPIPE
• HEIMLECK METHOD FOR CLEARING A BLOCKED AIR WAY
• DIAGRAM SWALLOWING

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STOMACH

• ESOPHAGUS PUSHES BOLUS INTO STOMACH
• A VALVE OPENS TO LET FOOD INTO STOMACH, VALVE
  CALLED CARDIAC SPHINCTER (VALVE CLOSES AFTER
  BOLUS ENTERS STOMACH)
• STOMACH IS A MUSCULAR , POUCHLIKE ENLARGEMENT OF
  THE DIGESTIVE TRACT
• gtgtHAS 3 CRIS-CROSSING LAYERS OF
• MUSCLE IN WALLS
• gtgtMUSCULAR WALLS MIX UP FOOD IN
• STOMACH (MECHANICAL
• DIGESTION)

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CHEMICAL DIGESTION IN STOMACH

• LINING OF STOMACH CONTAINS MILLIONS OF GLANDS
  THAT SECRETE A MIXTURE OF CHEMICALS CALLED
  GASTRIC JUICE
• GASTRIC JUICE CONTAINS HYDROCHLORIC ACID (HCl)
  AND PEPSIN
• HCl LIQUIFIES BOLUS INTO A SYRUPY MASS CALLED
  CHYME (STRONG ACID, HAS A pH 2)
• PEPSIN IS AN ENZYME THAT BEGINS THE CHEMICAL
  DIGESTION OF PROTEINS IN THE FOOD (CHANGES
  POLYPEPTIDES INTO DIPEPTIDES)

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• WALLS OF STOMACH PROTECTED FROM GASTRIC JUICE BY
  SECRETING A PROTECTIVE LAYER OF MUCOUS WHEN FOOD
  IS PRESENT
• FOOD REMAINS IN STOMACH FOR 2-4 HOURS
• gtgtDIGESTED, LIQUIFIED FOOD
• (CHYME) RELEASED SLOWLY INTO
• SMALL INTESTINE THROUGH
• VALVE BETWEEN STOMACH
• SMALL INTESTINE CALLED THE
• PYLORIC SPHINCTER

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SMALL INTESTINE

• MUSCULAR TUBE ABOUT 6 METERS LONG 2.5
  CENTIMETERS IN DIAMETER
• CHEMICAL AND MECHANICAL DIGESTION IS COMPLETED IN
  SMALL INTESTINE
• FIRST 25 cm OF SMALL INTESTINE CALLED THE
  DUODENUM
• gtgtAREA WHERE BILE DUCT
• PANCREATIC DUCT ENTER SMALL
• INTESTINE
• gtgtENZYMES PRODUCED IN THE
• PANCREAS AND LIVER ENTER
• SMALL INTESTINES AT THIS POINT

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• NO FOOD PASSES THROUGH LIVER OR PANCREAS
• WALLS OF SMALL INTESTINE ALSO PRODUCE ENZYMES FOR
  DIGESTION
• gtgt MALTASE, SUCRASE
• LACTASE CHANGE
• DISACCHARIDES INTO
• MONOSACCHARIDES
• gtgt PEPTIDASE CHANGES DIPEPTIDES
• INTO AMINO ACIDS
• gtgt NUCLEASE CHANGES NUCLEIC
• ACIDS INTO MONOSACCHARIDE
• NITROGEN BASES

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PANCREAS

• SOFT, FLATTENED GLAND
• SECRETES BOTH DIGESTIVE ENZYMES AND HORMONES
• SECRETES A MIXTURE OF ENZYMES CALLED PANCREATIC
  JUICE
• gtgtPANCREATIC AMYLASE CHANGES
• STARCH INTO DISACCHARIDE
• gtgtTRYPSIN CHANGES PROTEIN INTO
• DIPEPTIDES
• gtgtPANCREATIC LIPASE CHANGES
• FATS INTO FATTY ACIDS AND
• GLYCEROL

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• gtgtNUCLEASE CHANGES NUCLEIC
• ACIDS INTO SUGAR AND
• NITROGEN BASES
• PANCREAS ALSO SECRETES SODIUM HYDROGEN
  BICARBONATE ,WHICH NEUTRALIZES THE ACID FROM THE
  STOMACH TO PREVENT DAMAGE TO THE SMALL INTESTINES

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LIVER

• COMPLEX GLAND INVOLVED IN MANY OTHER BODY
  FUNCTIONS BESIDES DIGESTION
• PRODUCES BILE , WHICH IS A CHEMICAL THAT BREAKS
  FAT INTO SMALL FAT DROPLETS (INCREASES SURFACE
  AREA FOR BETTER DIGESTION LATER / MECHANICAL
  DIGESTION) ALSO HELPS NEUTRALIZE STOMACH ACID
• BILE STORED IN GALLBLADDER UNTIL NEEDED

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ABSORPTION OF NUTRIENTS

• FOOD DIGESTION IS COMPLETED IN THE SMALL
  INTESTINES (3-5 HRS.) AND TAKES THE FORM OF
  NUTRIENTS (MONOSACCHARIDES, AMINO ACIDS, FATTY
  ACIDS, GLYCEROL NITROGEN BASES) IN A WATERY
  SOLUTION
• PERISTALSIS SLOWLY MOVES MIXTURE THROUGH SMALL
  INTESTINE
• MIXTURE PASSES OVER THOUSANDS OF FINGERLIKE
  PROJECTIONS CALLED VILLI , LINNING THE INSIDE
  WALLS OF THE SMALL INTESTINE

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• VILLI ABSORB THE NUTRIENTS INTO THE BLOODSTREAM
  FOR CIRCULATION AROUND THE BODY
• VILLI CONTAIN MANY SMALL BLOOD VESSELS AT THEIR
  SURFACE WHICH ALLOWS NUTRIENTS TO PASS EASILY
  INTO BLOODSTREAM
• VILLI ALSO CONTAIN LYMPH VESSELS WHICH ALSO
  ABSORB FATTY ACIDS AND GLYCEROL , WHICH ARE
  CIRCULATED AROUND THE BODY IN A SEPARATE
  CIRCULATORY SYSTEM OF TISSUE FLUIDS (CALLED THE
  LYMPHATIC SYSTEM)

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LARGE INTESTINE

• INDIGESTIBLE MATERIAL PASSES INTO LARGE INTESTINE
• MUSCULAR TUBE, ALSO CALLED COLON
• ABOUT 1.5 METERS LONG, 6.5 cm IN DIAMETER
• APPENDIX MAY BE FOUND AT JUNCTION BETWEEN SMALL
  AND LARGE INTESTINE
• gtgtSMALL, FINGER-LIKE STRUCTURE
• gtgtNO FUNCTION IS A VESTIGIAL
• ORGAN REMAINS OF A ONCE
• FUNCTIONING ORGAN FROM OUR
• EVOLUTIONARY PAST

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• FUNCTION OF LARGE INTESTINE IS TO ABSORB WATER
  FROM INDIGESTABLE MIXTURE (REMAINING CHYME)
  THROUGH WALLS OF INTESTINE
• gtgtSOLID MATERIAL LEFT BEHIND,
• CALLED FECES
• gtgtE.coli BACTERIA LIVES IN LARGE
• INTESTINE AND MAKES VITAMINS B
• K FROM INDIGESTABLE
• MATERIAL, VITAMINS ABSORBED
• BY INTESTINES WITH WATER

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• FECES STORED IN PORTION OF LARGE INTESTINE CALLED
  THE RECTUM
• FECES ELIMINATED FROM THE RECTUM THROUGH THE ANAL
  SPHINCTER AND ANUS
• TEST 38.1 !!!!!

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SECTION 38.2

• THE CONTROL OF DIGESTION AND HOMEOSTASIS

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CONTROL OF DIGESTION

• THE SMELL , SIGHT OR THOUGHT OF FOOD INCREASES
  THE SECREATION OF SALIVA IN PREPERATION FOR
  EATING
• gtgtRESPONSE DUE TO BRAIN GLANDS
• gtgtSECRETION OF GASTRIC JUICE IN
• STOMACH UNDER CONTROL OF
• BOTH NERVOUS SYSTEM AND
• ENDOCRINE SYSTEM (SYSTEM OF
• GLANDS THAT SECRETE
• HORMONES THAT CONTROL CELL
• PROCESSES ACTIVITIES)

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• gtgtSIGHT OR SMELL OF FOOD
• STIMULATES SECRETION OF
• GASTRIC JUICE / RESPONSE
• CONTROLED BY NERVOUS SYSTEM
• ONCE FOOD IS IN STOMACH, NERVE RECEPTORS RESPOND
  TO STRECHING OF STOMACH WALLS AND SIGNAL BRAIN TO
  CONTINUE SECRETION OF GASTRIC JUICE

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• IF PROTEIN IS IN THE STOMACH, IT WILL STIMULATE
  GLANDS IN THE STOMACH WALLS TO SECRETE A HORMONE
  CALLED GASTRIN
• gtgtGASTRIN IS ABSORBED INTO THE
• BLOODSTREAM AND CAUSES THE
• GLANDS IN THE STOMACH WALLS
• TO CONTINUE TO SECRETE
• GASTRIC JUICE
• gtgtAS FOOD PASSES INTO SMALL
• INTESTINE, MORE HORMONES ARE
• SECRETED FROM WALLS OF SMALL
• INTESTINE (HORMONES ENTER
• BLOODSTREAM)

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• HORMONES FROM SMALL INTESTINE INHIBIT (STOP) THE
  SECRETION OF GASTRIC JUICE IN THE STOMACH AND
  STIMULATE THE PANCREAS TO SECRETE PANCREATIC
  JUICE AND THE PRODUCTION AND RELEASE OF BILE FROM
  THE LIVER

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ENDOCRINE CONTROL OF HOMEOSTASIS AND METABOLISM

• JUST AS HORMONES OF THE DIGESTIVE TRACT ARE
  DIRECTLY INVOLVED IN DIGESTION, HORMONES ALSO
  PLAY KEY ROLES IN MAINTAINING THE NECESSARY
  LEVELS OF NUTRIENTS IN THE BLOOD AND CONTROLING
  THE ENERGY EXCHANGE BETWEEN CELLS IN THE BODY.

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GLUCOSE (ENERGY) REGULATION

• MAINTANCE OF BLOOD GLUCOSE IS ACCOMPLISHED BY 2
  MEANS
• 1. EATING MEALS AT REGULAR
• INTERVALS DURING THE DAY
• gtgtPROVIDES CONSTANT SUPPLY
• THROUGH DIGESTION
• 2. HORMONES
• gtgtCONTROLS AMOUNT OF GLUCOSE IN
• BLOODSTREAM / BODY

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• GLYCOGEN IS A POLYSACCHARIDE AND IS THE FORM IN
  WHICH SUGARS ARE STORED IN THE LIVER AND MUSCLE
• gtgtWHEN BODY NEEDS ENERGY,
• GLYCOGEN BROKEN DOWN INTO
• GLUCOSE, WHICH IS
• TRANSPORTED BY BLOOD TO FUEL
• CELL PROCESSES THROUGHOUT
• THE BODY
• gtgtRELEASE OF GLUCOSE FROM
• LIVER INTO BLOODSTREAM
• CONTROLLED BY HORMONES
• CALLED GLUCAGON AND INSULIN
• (PRODUCED IN PANCREAS)

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• WHEN PANCREAS SECRETES DIGESTIVE ENZYMES
  (PANCREATIC JUICE) INTO THE SMALL INTESTINE
  THROUGH THE PANCREATIC DUCT IT IS CALLED AN
  EXOCRINE GLAND
• WHEN THE PANCREAS SECRETE HORMONES INTO THE
  BLOODSTREAM IT IS CALLED AN ENDOCRINE GLAND
• gtgtDUCTLESS GLANDS
• gtgtHORMONES RELEASED DIRECTLY
• INTO BLOODSTREAM
• gtgtHORMONES GIVE INFORMATION TO
• SPECIFIC CELLS IN BODY CALLED
• TARGET TISSUES

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• PHYSICAL ACTIVITY WILL CAUSE SECRETION OF
  HORMONES TO VARY
• EX. INCREASED ACTIVITY WILL RESULT
• IN INCREASED GLUCAGON WHICH
• RESULTS IN MORE GLUCOSE
• AVAILABLE TO CELLS
• gtgtCAUSES GLYCOGEN TO BE
• BROKEN DOWN INTO GLUCOSE
• IN LIVER
• EX. DECREASED ACTIVITY WILL RESULT
• IN DECREASE OF GLUCAGON AND
• THE INCREASE OF INSULIN
• gtgtINSULIN LOWERS BLOOD SUGAR
• LEVELS BY CAUSING EXCESS
• GLUCOSE TO BE CONVERTED
• INTO GLYCOGEN (AND STORED
• IN LIVER)

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• AFTER A MEAL BLOOD SUGAR LEVELS RISE
• gtgtPANCREAS BETA CELLS SECRETE
• INSULIN WHICH ENABLES CELLS TO
• ABSORB GLUCOSE
• gtgtINSULIN ALSO CONVERT EXCESS
• GLUCOSE INTO GLYCOGEN TO BE
• STORED IN THE LIVER

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• WHEN BLOOD SUGAR LEVELS BECOME LOW (BETWEEN
  MEALS) PANCREAS ALPHA CELLS SECRETE GLUCAGON
• gtgtGLUCAGON CAUSES STORED
• GLYCOGEN IN THE LIVER TO BE
• CONVERTED INTO GLUCOSE
• gtgtLIVER THEN RELEASES GLUCOSE
• INTO BLOODSTREAM, BLOOD
• SUGAR LEVELS RISE
• CONTROL OF BLOOD SUGAR LEVELS BY PANCREAS HELPS
  BODY MAINTAIN ITS HOMEOSTASIS

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DIABETES

• GLUCOSE CANNOT DO ITS JOB (PROVIDE ENERGY TO
  CELLS) WITHOUT INSULIN (ENABLES GLUCOSE TO ENTER
  CELLS)
• SOMETIMES PANCREAS DOESNT PRODUCE ENOUGH
  INSULIN, CAUSES BLOOD SUGAR LEVEL (GLUCOSE) TO
  RISE
• gtgtCONDITION CALLED DIABETES
• gtgtLARGE AMOUNTS OF SUGAR
• EXCRETED IN URINE

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• LACK OF INSULIN ALSO AFFECTS HYPOTHALAMUS GLAND
  LOCATED AT BASE OF BRAIN
• gtgtREGULATES APPETITE
• gtgtLACK OF INSULIN PREVENTS
• PREVENTS GLUCOSE IN BLOOD FROM
• ENTERING CELLS OF HYPOTHALAMUS,
• SO PERSON WITH DIABETES GETS
• HUNGRY EATS CONSTANTLY, BUT IS
• ACTUALLY STARVING BECAUSE
• GLUCOSE CANNOT ENTER ANY CELLS
• TO PROVIDE ENERGY

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• gtgtRESULTS IN RAPID WEIGHT LOSS, ALONG WITH GREAT
  THIRST AND HUNGER (SYMPTOMS OF DIABETES)
• INSULIN GIVEN TO HELP MAINTAIN NORMAL BLOOD SUGAR
  LEVELS

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• INTERNET ASSIGNMENT (WORTH 30 PTS)
• 1. WRITE A ONE PAGE REPORT ON THE
• A) TYPES OF DIABETES ?
• (NAME DESCRIBE SYMPTOMS)
• B) CAUSES OF DIABETES ?
• (DESCRIBE FOR EACH TYPE)
• C) TREATMENTS FOR DIABETES ?
• (DESCRIBE FOR EACH TYPE)
• 2. USE THE INTERNET (SEARCH ENGINE)
• TYPE IN CAUSES OF DIABETES IN
• SEARCH ENGINE WINDOW
• 3. SEND REPORT TO BIOLOGY FOLDER
• ON NETWORK

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METABOLIC CONTROL

• THYROID GLAND REGULATES METABOLISM AND ENERGY
  BALANCE, GROWTH AND DEVELOPMENT, AND THE GENERAL
  ACTIVITY OF THE NERVOUS SYSTEM
• THE MAIN METABOLIC AND GROWTH HORMONE OF THE
  THYROID IS THYROXINE
• gtgtAFFECTS RATE AT WHICH BODY
• USES ENERGY
• gtgtALSO DETERMINES FOOD INTAKE
• REQUIREMENTS

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• THYROID ALSO SECRETES THE HORMONE CALCITONIN
• gtgtREGULATES CALCIUM AND
• PHOSPHATE LEVELS IN BLOOD
• gtgtCALCIUM NECESSARY FOR
• BLOOD CLOTTING, FORMATION
• OF BONES AND TEETH, AND
• NORMAL MUSCLE AND NERVE
• FUNCTION

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• PARATHYROID GLANDS SECRETE HORMONE WHICH ALSO
  REGULATES CALCIUM AND PHOSPHATE LEVELS IN BLOOD
• gtgtCALLED PTH (PARATHYROID
• HORMONE)
• gtgtINREASES THE RATE OF
• CALCIUM, PHOSPHATE, AND
• MAGNESIUM ABSORPTION IN
• SMALL INTESTINES AND THE
• RELEASE OF CALCIUM AND
• PHOSPHATE FROM BONES
• gtgtALSO CONTROLS KIDNEY
• FUNCTION
• TEST 38.2 !!!!!

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SECTION 38.3

• NUTRITION

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VITAL NUTRIENTS

• 6 KINDS OF NUTRIENTS FOUND IN FOODS
• 1. CARBOHYDRATES
• 2. FATS
• 3. PROTEINS
• 4. MINERALS
• 5. VITAMINS
• 6. WATER
• ABOVE 6 NUTRIENTS ESSENTIAL TO CHEMICAL REACTIONS
  IN BODY
• THESE NUTRIENTS SUPPLIED TO BODY WHEN WE EAT
  FOODS FROM THE 5 MAIN FOOD GROUPS

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5 MAIN FOOD GROUPS

• 1. MILK GROUP
• gtgtPROVIDES CARBOHYDRATES,
• CALCIUM, VITAMIN B2, PROTEIN
• FAT
• EX. MILK, YOGURT, CHEESE
• 2. MEAT GROUP
• gtgtPROVIDES PROTEIN, NIACIN, IRON,
• VITAMIN B1 FAT
• EX. CHICKEN, FISH, BEEF, EGGS
• 3. VEGETABLE GROUP
• gtgtPROVIDES VITAMINS A C,
• CARBOHYDRATE, PROTEIN FIBER
• EX. CARROTS, SPINACH, TOMATOES

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• 4. FRUIT GROUP
• gtgtPROVIDES VITAMINS A C,
• CARBOHYDRATE, CALCIUM, PROTEIN FIBER
• EX. BANANAS, APPLES, GRAPES,
• ORANGES
• 5. GRAIN GROUP
• gtgtPROVIDES CARBOHYDRATE, VITAMIN
• B1, IRON, PROTEIN NIACIN
• EX. BREADS, BAGELS, CEREALS
• SELECT FOODS FROM THE 5 FOOD GROUPS AND YOU
  WILL HAVE A HEALTHFUL DIET THAT SUPPLIES THE 6
  ESSENTIAL NUTRIENTS YOUR BODY NEEDS

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CARBOHYDRATES

• CARBOHYDRATES INCLUDE STARCHES AND SIMPLE SUGARS
• STARCHES ARE COMPLEX CARBOHYDRATES , LONG CHAINS
  OF MOLECULES
• SIMPLE SUGARS ARE SIMPLE CARBOHYDRATES , SHORT
  CHAINS OF MOLECULES OR SINGLE MOLECULES
• CARBOHYDRATES ARE IMPORTANT SOURCE OF ENERGY FOR
  ALL BODY CELLS

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• DURING DIGESTION, COMPLEX CARBOHYDRATES BROKEN
  DOWN INTO SIMPLE SUGARS (GLUCOSE, FRUCTOSE,
  GALACTOSE)
• SIMPLE SUGARS ABSORBED INTO BLOOD STREAM THROUGH
  VILLI OF SMALL INTESTINE
• SIMPLE SUGARS CIRCULATE THROUGHOUT BODY TO FUEL
  BODY FUNCTIONS
• SIMPLE SUGARS CARRIED TO LIVER WHERE THEY ARE
  CONVERTED TO AND STORED AS GLYCOGEN

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• CELLULOSE IS ANOTHER COMPLEX CARBOHYDRATE FOUND
  IN ALL PLANT CELL WALLS
• gtgtNOT DIGESTABLE BY HUMANS
• gtgtBUT STILL IMPORTANT IN OUR
• DIET, PROVIDES FIBER
• gtgtPROVIDES BULK IN OUR DIET THAT
• STIMULATES THE DIGESTIVE
• TRACT (PARASTALSIS) AND HELPS
• IN THE ELIMINATION OF WASTES
• (FECES)

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FATS

• FATS ARE AN ESSENTIAL NUTRIENT
• PROVIDE ENERGY FOR BODY AND USED AS A BUILDING
  MATERIAL
• gtgtUSED TO MAKE CELL
• MEMBRANES
• gtgtUSED IN GLANDS TO MAKE
• HORMONES
• gtgtPROTECT BODY FROM INJURY
• gtgtINSULATE BODY AGAINST COLD

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• FATS BROKEN DOWN INTO FATTY ACIDS AND GLYCEROL
  AND ABSORBED BY VILLI OF SMALL INTESTINE (LYMPH
  VESSELS)
• SOME FATTY ACIDS END UP IN LIVER AND ARE
  CONVERTED INTO GLYCOGEN , OTHER FATTY ACIDS ARE
  STORED AS FAT DEPOSITS THROUGHOUT BODY

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PROTEINS

• BODY HAS MANY USES FOR PROTEINS, USED IN ENZYMES,
  HORMONES, TO CLOT BLOOD AND FOR ANTI BODIES IN
  THE IMMUNE SYSTEM
• PROTEINS ARE ALSO APART OF MUSCLE AND MANY CELL
  STRUCTURES (ALL CELL ORGANELLES INCLUDING CELL
  MEMBRANE)
• PROTEINS BROKEN DOWN IN DIGESTION INTO AMINO
  ACIDS

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• AMINO ACIDS ABSORBED BY SMALL INTESTINES INTO
  BLOOD STREAM AND CARRIED TO LIVER
• LIVER CAN CONVERT AMINO ACIDS INTO FATS OR
  GLUCOSE FOR ENERGY IF OTHER ENERGY SUPPLIES ARE
  USED UP
• MOST AMINO ACIDS ABSORBED BY CELLS AND USED FOR
  THE MAKING OF PROTEINS (PROTEIN SYNTHESIS)

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MINERALS VITAMINS

• MINERALS AN INORGANIC SUBSTANCE THAT SERVES AS
  A BUILDING MATERIAL OR TAKES PART IN CHEMICAL
  REACTIONS IN THE BODY
• MAKES UP ABOUT 4 OF YOUR TOTAL BODY WEIGHT
• MOST MINERAL CONTENT IN SKELETON (CALCIUM ,
  PHOSPHORUS)
• MINERALS NOT USED FOR ENERGY

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VITAL MINERALS
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VITAMINS

• ORGANIC NUTRIENT
• NEEDED IN SMALL AMOUNTS TO MAINTAIN GROWTH AND
  METABOLISM
• ALSO CALLED COENZYMES , CHEMICALS THAT HELP
  FACILITATE (SPEED UP CONTROL) A CHEMICAL
  REACTION

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VITAL VITAMINS
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WATER

• MOST ABUNDANT SUBSTANCE IN BODY
• MAKES UP 60 OF RED BLOOD CELLS AND 75 OF MUSCLE
  CELLS
• PLAYS MAJOR ROLE IN MANY CHEMICAL REACTIONS,
  NECESSARY FOR DIGESTION OF FOOD
• CARRIES OXYGEN AND NUTRIENTS THROUGHOUT BODY IN
  PLASMA PART OF BLOOD AND TISSUE FLUID
• ABSORBS AND RELEASES HEAT SLOWLY, HELPS REGULATE
  BODY TEMPERATURE

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• BODY LOSES ABOUT 2.5 L OF WATER PER DAY THROUGH
  BREATHING, SWEATING URINE, MUST BE CONSTANTLY
  REPLACED

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METABOLISM CALORIES

• METABOLISM IS THE SUM OF ALL THE CHEMICAL
  REACTIONS THAT OCCUR IN YOUR BODY
• SOME OF THESE REACTIONS BREAKDOWN MATERIALS INTO
  SIMPLER FORMS (HYDROLYSIS)
• OTHER REACTIONS MAKE MORE COMPLEX SUBSTANCES OUT
  OF SIMPLER ONES (DEHYDRATION SYNTHESIS)
• THE ENERGY CONTENT OF FOOD IS MEASURED IN UNITS
  CALLED CALORIES

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• FOODS WHICH CONTAIN FATS AND CARBOHYDRATES
  CONTAIN MANY MORE CALORIES THAN OTHERS
• 1 GRAM OF FAT CONTAINS 9 CALORIES
• 1 GRAM OF CARBOHYDRATE OR PROTEIN CONTAINS 4
  CALORIES
• ACTUAL NUMBER OF CALORIES NEEDED EACH DAY VARIES
  FROM PERSON TO PERSON DEPENDING ON THE PERSONS
  WEIGHT, AGE, SEX, LEVEL OF PHYSICAL ACTIVITY
• IN GENERAL, MALES NEED MORE CALORIES PER DAY THAN
  FEMALES
• EX. FEMALES 2000-2500 CALORIES / DAY
• EX. MALES 2500-3500 CALORIES / DAY

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• TEENAGERS NEED MORE CALORIES THAN ADULTS PER DAY
• ACTIVE PEOPLE NEED MORE CALORIES THAN INACTIVE
  PEOPLE PER DAY
• IF YOU EAT MORE CALORIES THAN YOUR BODY CAN
  METABOLIZE, YOULL STORE THE EXTRA ENERGY AS BODY
  FAT AND GAIN WEIGHT
• IF YOU EAT FEWER CALORIES THAN YOUR BODY CAN
  METABOLIZE, YOU WILL USE SOME OF THE ENERGY
  STORED IN BODY FAT AND LOSE WEIGHT
• TEST 38.3 !!!!!!