Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
The Remarkable Body Chapter 3 Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Learning Objectives Describe the levels of organization in the body, and identify some basic ways in which nutrition supports them. Describe the relationship between the body’s fluids and the cardiovascular system and their important to the nourishment and maintenance of body tissues. Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Learning Objectives Summarize the interactions between the nervous and hormonal systems and nutrition. State how nutrition and immunity are interrelated, and describe the importance of inflammation to the body’s health. Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Learning Objectives Compare the terms mechanical digestion and chemical digestion, and point out where these processes occur along the digestive tract with regard to carbohydrate, fat, and protein. Name some common digestive problems and off suggestions for dietary alterations that may improve them. Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Learning Objectives Identify the excretory functions o the lungs, liver, kidneys, and bladder, and state why they are important to maintain normal body functioning. Identify glycogen and fat as the two forms of nutrients stored in the body, and identify the liver, muscles, and adipose tissue as the body tissues that store them. Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Learning Objectives Define the term moderate alcohol consumption, and discuss the potential health effects, both negative and positive, associated with this level of drinking. Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Body’s Cells Body is composed of trillions of cells Body needs nutrients Cells are self-contained, living entities Depend on one another Basic needs Essential nutrients Cells die at varying rates Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney A Cell (Simplified Diagram) Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Body’s Cells Genes Control Functions Direct production of proteins Provide instruction for structural components of cells Affects how body handles nutrients Complete set of genes in each cell Gene variations Inborn error of metabolism Influence of nutrients Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney From DNA to Living Cells Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Body’s Cells Cells, tissues, organs, systems Cells into tissues Tissues into organs Organs together as part of body systems Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Body Fluids and the Cardiovascular System Body fluids Supply energy, oxygen, nutrients, and water Deliver fresh supplies and pick up wastes Circulating fluids Blood Arteries, veins, capillaries Plasma Lymph Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Blood Flow in the Cardiovascular System Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Body Fluids and the Cardiovascular System Plasma Extracellular fluid Intracellular fluid All cell reactions take place Holds cellular shape Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Body Fluids and the Cardiovascular System All blood circulates to the lungs Picks up oxygen Releases carbon dioxide Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Body Fluids and the Cardiovascular System Blood returns to heart Blood pumped to rest of body Delivers nutrients & picks up wastes Blood passes through digestive system Picks up nutrients Except for fats Fats travel via lymph Routed directly to liver Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Lymph Vessels and the Bloodstream Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Body Fluids and the Cardiovascular System Kidneys Cleansing of wastes Fluid intake Red blood cell life expectancy Blood is sensitive to malnutrition Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Hormonal and Nervous Systems Hormones Chemical messengers Secreted and released directly into blood by glands Stimulate organs to take action Glands monitor conditions in the body Pancreas Insulin and glucagon Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Hormonal and Nervous Systems Nutrition affects the hormonal system Hormones affect nutrition Examples Nervous system Receives and integrates information from sensory receptors Role in hunger regulation Cortex and hypothalamus Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Cutaway Side View of the Brain Showing the Hypothalamus & Cortex Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Hormonal and Nervous Systems Fight-or-flight reaction (stress response) Neurotransmitters Epinephrine and norepinephrine Metabolism speeds up Organ response Eyes, heart, liver, stomach Heart disease Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Immune System Cooperation among tissues to maintain defenses Physical barriers Antigen Immune defenses White blood cells Phagocytes Lymphocytes (T-cells and B-cells) Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Immune System Inflammation Response to injury or irritation Increased white blood cells, redness, heat, pain, swelling Normal and healthy response Problem with chronic inflammation Dietary factors Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Digestive System Five basic chemical tastes Sweet, sour, bitter, salty, and umami Other factors affecting experience of food flavor Sweet, salty, and fatty foods Almost universally desired Can lead to drastic overeating of these substances Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Innate Preference for Sweet Taste Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Digestive System Digestive tract Flexible, muscular tube Path Total length of about 26 feet Body surrounds digestive canal System’s job is to digest food to its components, absorb, and excrete System works at two levels Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Digestive System Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Digestive System Mechanical digestion Begins in the mouth Chewing Stomach and small intestine Peristalsis Chyme travels through pyloric valve Large intestine Digestion is virtually continuous Sleep and exercise Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Peristaltic Wave Passing Down the Esophagus and Beyond Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Muscular Stomach Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Digestive System Chemical digestion Digestive juices Salivary glands, stomach, pancreas, liver, and small intestine Mouth Saliva – starches and fat Saliva – health of teeth Stomach Hydrochloric acid – protein Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney pH Values of Digestive Juice and Other Common Fluids Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Digestive System Chemical digestion Intestine Bile Pancreatic juice Digestive enzymes in wall of intestine Fiber Food combinations and digestion Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney “I Am What I Eat” Within 24 to 48 hours 90% of carbs, fat, and protein are digested and absorbed Mouth Food is crushed, mashed, and mixed with saliva Carbohydrate digestion begins Swallowing Peristalic waves Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney “I Am What I Eat” Stomach Gastric juice mixes with food Unwinds proteins Chyme Small intestine Bile from the liver Pancreas Large intestine Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Typical Digestive System Transit Times Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney “I Am What I Eat” Absorption Nutrient molecules transverse intestinal lining Water-soluble components Fat-soluble components Cells of small intestine are selective Folded structure Villi Microvilli Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Details of the Small Intestine Lining Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney “I Am What I Eat” Transport Lymph vessels Products of fat digestion Fat-soluble vitamins Blood vessels Products of carbohydrate & protein digestion Most vitamins Minerals Nourishment of digestive tract Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney A Letter from Your Digestive Tract Hiccups Fiber and gas Heartburn Antacids GERD Ulcers Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney A Letter from Your Digestive Tract Choking Constipation & diarrhea Hemorrhoids Irritable bowel syndrome (IBS) Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Normal Swallowing and Choking Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney First Aid for Choking Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Excretory System Organs involved in waste removal Lungs, liver, kidneys Kidneys Waste materials are dissolved in water Working units – nephrons Urine is stored in bladder Sodium and blood pressure Work regulated by hormones Importance of water supply Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Storage Systems Eating intervals of 4-6 hours Major storage sites Liver – carbohydrates Glycogen Muscles – carbohydrates Glycogen Fat cells – fat and fat-related substances Variations in nutrient stores Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Alcohol and Nutrition: Do the Benefits Outweigh the Risks? Controversy 3 Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney U.S. Alcohol Consumption Total daily energy intake as alcohol U.S. average of 6 to 10 percent Drinking pattern Binge drinking Heavy drinking Moderate drinking Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Does Moderate Alcohol Use Benefit Health? Influence of age Influence of drinking patterns Middle-aged people Light to moderate intakes Health benefits of wine Science is mixed Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney What is Alcohol? Names end in –ol Act as lipid solvents Ethanol Alcoholic beverages Social interactions Nonalcoholic beverages Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney What is a “Drink”? Beverage volume Proof Percentage of alcohol Defining a drink Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Drinking Patterns Defining moderation Difficulties with defining Health authority definition Problem drinkers and alcoholism Irrational and dangerous behaviors Health effects Heavy episodic drinking Defined Harms Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Behaviors Typical of Moderate Drinkers and Problem Drinkers Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Immediate Effects of Alcohol The body gives special attention to alcohol Diffusion through stomach walls Reach brain within a minute Vomiting Presence of food in the stomach Absorption in small intestine Alcohol dehydrates tissues Increased urine output Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Alcohol Arrives in the Brain Nerves Inhibitory Excitatory Lethal dose Speed and amount consumed Toxicity, oxidative stress, and the brain Brain tissue shrinks Brain inflammation Accidents Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Effects of Rising Blood Alcohol Levels on the Brain Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Alcohol Doses and Average Blood Level Percentages Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Blood Alcohol and Traffic Accidents Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Alcohol Arrives in the Body Liver processes most of the body’s alcohol Alcohol breakdown in the stomach Alcohol dehydrogenase (ADH) Acetaldehyde Women vs. men Excretion in breath and urine Rate of alcohol clearance Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Alcohol Breakdown Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Alcohol Affects the Liver Alcohol metabolism generates damaging free radicals Diseases and organ damage Fatty liver Liver fibrosis Cirrhosis Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney The Hangover Mild form of drug withdrawal Contributors to hangovers Congeners Dehydration Formaldehyde Methanol Sure cure for hangover Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Alcohol’s Long-Term Effects Effects in pregnancy Effects on heart and brain Cancer Even moderate consumption increases risk Long-term effects of alcohol abuse Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Alcohol’s Effects on Nutrition Causes disturbances in nutrition All discretionary calories Fattening power of alcohol “Beer belly” Effects on vitamins Malnutrition Wernicke-Korsakoff syndrome Folate Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney Calories in Alcoholic Beverages and Mixers Nutrition: Concepts & Controversies, 13th edition, Sizer & Whitney