PowerPoint Lecture Outlines to accompany Hole’s Human Anatomy and Physiology Eleventh Edition Shier w Butler w Lewis Chapter Copyright © The McGraw-Hill Companies, Inc.
Download ReportTranscript PowerPoint Lecture Outlines to accompany Hole’s Human Anatomy and Physiology Eleventh Edition Shier w Butler w Lewis Chapter Copyright © The McGraw-Hill Companies, Inc.
PowerPoint Lecture Outlines to accompany Hole’s Human Anatomy and Physiology Eleventh Edition Shier w Butler w Lewis Chapter 18 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1 Chapter 18 Nutrition and Metabolism Nutrients – chemical substances supplied by the environment required for survival Macronutrients • carbohydrates • proteins • fats Micronutrients • vitamins • minerals Essential Nutrients • nutrients human cells cannot synthesize such as certain amino acids 2 Substances Controlling Appetite 3 Hormones Control Body Weight 4 Carbohydrates Organic compounds primarily used to supply cellular energy Sources • sugars • starches • usually from plant sources • glycogen in meats RDA is 125-175g Excesses lead to • obesity • dental caries • nutritional deficits Deficiencies lead to • metabolic acidosis • weight loss 5 Carbohydrate Utilization • oxidized for energy • production of certain molecules (ribose, deoxyribose) • stored in liver and muscles as glycogen • converted to fats and stored in adipose tissue 6 Carbohydrate Utilization 7 Lipids Organic compounds that supply energy and are used to build cell structures Excesses lead to Sources • obesity • meats • increased serum • eggs cholesterol • milk • increased risk of • lard heart diseases • plant oils RDA is 80-100g Deficiencies lead to • weight loss • skin lesions • hormonal imbalances 8 Lipid Utilization • oxidized for energy • production of triglycerides, phospholipids, lipoproteins, and cholesterol • stored in adipose tissue • glycerol may be used to synthesize glycerol 9 Lipid Utilization 10 Lipid Utilization The liver uses fatty acids to synthesize a variety of lipids. 11 Proteins Organic compounds that serve as structural materials, act as enzymes, and provide energy Sources • meats • cheeses • nuts • legumes RDA is 0.8g/kg body weight or 10% of diet Excesses lead to obesity Deficiencies lead to • extreme weight loss • muscle wasting • anemia • growth retardation 12 Protein Utilization • build cell structures • enzymes • hormones • transport of oxygen • regulation of water balance • control of pH • formation of antibodies • can be converted to carbohydrates or fats • may be broken down and oxidized for energy 13 Protein Utilization 14 Protein Utilization 15 Nitrogen Balance • amount of nitrogen taken in is equal to amount excreted • negative nitrogen balance develops from starvation • positive nitrogen balance develops in growing children, pregnant women, or an athlete in training 16 Carbohydrate, Lipid and Protein Nutrients 17 Energy Values of Food Calorie – indicates amount of potential energy a food contains Carbohydrates 4.1 calories per gram Lipids 9.5 calories per gram Proteins 4.1 calories per gram 18 Energy Requirements Basal metabolic rate (BMR) • rate at which body expends energy at rest • primarily reflects energy needed to support activities of organs • varies with gender, body size, body temperature, and endocrine function Energy needed • to maintain BMR • to support muscular activity • to maintain body temperature • for growth in children and pregnant women 19 Energy Balance • occurs when caloric intake in the form of food equals caloric output from BMR and muscular activities • positive energy balance leads to weight gain 20 Desirable Weight • most common nutritional disorders involve caloric imbalances • overweight is defined as exceeding desirable weight by 10% - 20% • obesity occurs when person is 20% above desired weight due to excess adipose tissue 21 Vitamins • Organic compounds (other than carbohydrates, lipids and proteins) that are essential for normal metabolic processes • Cannot be synthesized by body cells in adequate amounts 22 Fat-Soluble Vitamins • carried in lipids • fairly resistant to heat (not destroyed by cooking and food processing • include Vitamins A, D, E, and K 23 Fat Soluble Vitamins Vitamin A • synthesized from carotenes • stored in liver • necessary for visual pigments • necessary for bone and teeth development • necessary for maintenance of epithelial cells • excesses lead to nausea, headache, dizziness, hair loss, birth defects • deficiencies lead to night blindness and degeneration of epithelial tissues Vitamin D • group of steroids • stored in liver, brain, skin, spleen, and bone • promotes absorption of calcium and phosphorus • necessary for bone and teeth development • excesses lead to diarrhea, calcification of soft tissues, and renal damage • deficiencies lead to bone weakening 24 Fat-Soluble Vitamins Vitamin E • stored in muscles and adipose tissue • prevents oxidation of vitamin A and some fatty acids • may help stability of cell membranes • excesses lead to nausea, headache, fatigue, easy bruising and bleeding • deficiencies are rare Vitamin K • stored in liver • necessary for prothrombin synthesis • excesses lead to jaundice • deficiencies lead to prolonged clotting time 25 Sources of Fat-Soluble Vitamins Vitamin A • liver • fish • milk • leafy green vegetables • yellow and orange vegetables and fruits Vitamin K • liver • soy oil • egg yolk • leafy green vegetables • tomatoes • cauliflower Vitamin E • cereal seed oils • salad oils • margarine • shortening • fruits • nuts • vegetables Vitamin D • skin • egg yolk • milk • fish liver oils 26 Water-Soluble Vitamins • include the B vitamins and vitamin C • B vitamins are several compounds essential for normal cellular metabolism • known as the vitamin B complex 27 Water-Soluble Vitamins Thiamine • vitamin B1 •coenzyme for carbohydrate oxidation •excesses are uncommon, include vasodilation and cardiac dysrhythmias • deficiencies lead to Beriberi, muscular weakness, heart enlargement Riboflavin • vitamin B2 • parts of enzymes and coenzymes (FAD) •deficiencies lead to dermatitis and blurred vision 28 Water-Soluble Vitamins Niacin • vitamin B3 •parts of coenzymes (NAD) •excesses lead to flushing, vasodilation, wheezing, or liver problems •deficiencies lead to pellagra, dermatitis, diarrhea, or mental disorders Pantothenic Acid • vitamin B5 •part of coenzyme A • deficiencies are rare; may lead to loss of appetite, mental depression and muscle spasms 29 Water-Soluble Vitamins Vitamin B6 • group of three chemically similar compounds • part of coenzymes needed for synthesis of proteins •excesses lead to numbness, clumsiness and paralysis • deficiencies lead to vomiting and convulsions Cyanocobalamin • vitamin B12 • part of coenzyme needed for nucleic acid synthesis • plays role in myelin sheath formation • needed for RBC formation • deficiencies lead to pernicious anemia 30 Water-Soluble Vitamins Folacin • folic acid • coenzyme required for amino acid and nucleic acid metabolism • needed for normal RBC production • deficiencies lead to megaloblastic anemia Biotin • coenzyme required for metabolism of amino acids, fatty acids, and nucleic acids • deficiencies are rare; may lead to elevated blood cholesterol, fatigue, nausea, and anorexia 31 Water-Soluble Vitamins Ascorbic acid • Vitamin C • needed for collagen production and metabolism of some amino acids • promotes absorption of iron and synthesis of hormones from cholesterol • deficiencies lead to scurvy, lowered resistance, and slow wound healing 32 Sources of Water-Soluble Vitamins Thiamine • meats • liver • leafy green vegetables • eggs • cereals • legumes Niacin • liver • meats • peanuts • legumes Riboflavin • milk • leafy green vegetables • meats Pantothenic acid • meats • cereals • legumes • milk • vegetables 33 Sources of Water-Soluble Vitamins Vitamin B6 • meats • cereals • peanuts • milk • bananas • avocados Folacin • cereals • legumes • milk • leafy green vegetables Cyanocobalamin • meats • milk • liver • cheese • eggs Biotin • egg yolk • liver • legumes • nuts • mushrooms 34 Sources of Water-Soluble Vitamins Ascorbic acid • egg yolk • liver • legumes • nuts • mushrooms 35 Minerals • inorganic elements that are essential in human metabolism • usually extracted from the soil by plants • obtained by humans from plant foods or animals that have eaten plants • responsible for roughly 4% of body weight 36 Minerals Major Minerals • calcium • phosphorus • potassium • sulfur • sodium • chlorine • magnesium Trace Elements • iron • manganese • copper • iodine • cobalt • zinc • fluorine • selenium • chromium 37 Major Minerals Calcium • mostly in inorganic salts of bones and teeth • needed for bone structure • essential for nerve impulse conduction • essential for muscle fiber contraction • essential for blood coagulation • increases permeability of cell membranes • activates certain enzymes • excesses lead to kidney stones, deposition of calcium phosphate in soft tissues • deficiencies lead to stunted growth, misshapen or fragile bones or tetany 38 Major Minerals Phosphorus • mostly in inorganic salts of bones and teeth • needed for structure of bones and teeth • component in nearly all metabolic processes • constituent of ATP, nucleic acids, many proteins, enzymes, and some vitamins • deficiency leads to stunted growth 39 Major Minerals Potassium • widely distributed • maintains intracellular osmotic pressure and pH • promotes metabolism • required for muscle contraction and nerve impulse conduction • excesses are uncommon • deficiency leads to muscular weakness, cardiac abnormalities, and edema 40 Major Minerals Sulfur • widely distributed • abundant in skin, nails, and hair • component of certain amino acids, thiamine, biotin, and mucopolysaccharides 41 Major Minerals Sodium • widely distributed • maintains osmotic pressure of extracellular fluids • regulates water movement in and out of cells • required for nerve impulse conduction and contraction of muscle fibers •excesses lead to edema, hypertension and shrinkage of body cells • deficiency leads to muscle cramps and convulsions 42 Major Minerals Chlorine • most concentrated in cerebrospinal fluid and gastric juice • helps maintain osmotic pressure of extracellular fluids • regulates pH • essential for formation of hydrochloric acid • aids in transport of carbon dioxide • deficiency leads to muscle cramps 43 Major Minerals Magnesium • abundant in bones • required in metabolic reactions for ATP production • helps breakdown of ATP to ADP • excess leads to diarrhea • deficiency leads to neuromuscular disturbances 44 Trace Elements • are essential minerals found in minute amounts • each makes up less than 0.005% of body weight • include • iron • manganese • copper • iodine • cobalt • zinc • fluorine • selenium • chromium 45 Trace Elements Iron • part of hemoglobin • catalyzes formation of vitamin A • incorporated into some enzymes Manganese • occurs in enzymes required for fatty acid and cholesterol synthesis, formation of urea, and functioning of the nervous system Copper • essential for hemoglobin synthesis, bone development, melanin production and myelin formation 46 Trace Elements Iodine • component of thyroid hormone Cobalt • required for synthesis of several enzymes Zinc • component of many enzymes • necessary for wound healing and maintaining integrity of skin 47 Trace Elements Fluorine • component of tooth structure Selenium • occurs in enzymes Chromium • essential for use of carbohydrates 48 Healthy Eating 49 Malnutrition • poor nutrition • undernutrition – deficiency of essential nutrients • overnutrition – excess of nutrient intake • primary malnutrition – malnutrition from diet alone • secondary malnutrition – adequate diet but individual characteristics make diet insufficient 50 Starvation • healthy human can survive 50-70 days without food • symptoms include low blood pressure, slow pulse, chills, dry skin, hair loss, and poor immunity • marasmus – lack of all nutrients • kwashiorkor – protein starvation • anorexia nervosa – eating disorder; self-starvation • Bulimia – eating disorder; bingeing and purging 51 Life-Span Changes • BMR rises in early childhood and peaks in adolescence • BMR declines in adulthood • change in nutrition often reflects effects of medical conditions and social and economic circumstances 52