1. The Remarkable Body
Chapter 3

2. 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.

3. 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.

4. 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.

5. 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.

6. Learning Objectives
Define the term moderate alcohol consumption, and discuss the potential health effects, both negative and positive, associated with this level of drinking.

7. 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

8. A Cell (Simplified Diagram)

9. 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

10. From DNA to Living Cells

11. The Body’s Cells Cells, tissues, organs, systems Cells into tissues
Tissues into organs
Organs together as part of body systems

12. The Body Fluids and the Cardiovascular System
Supply energy, oxygen, nutrients, and water
Deliver fresh supplies and pick up wastes
Circulating fluids
Blood
Arteries, veins, capillaries
Plasma
Lymph

13. Blood Flow in the Cardiovascular System

14. The Body Fluids and the Cardiovascular System
Plasma
Extracellular fluid
Intracellular fluid
All cell reactions take place
Holds cellular shape

15. The Body Fluids and the Cardiovascular System
All blood circulates to the lungs
Picks up oxygen
Releases carbon dioxide

16. 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

17. Lymph Vessels and the Bloodstream

18. The Body Fluids and the Cardiovascular System
Kidneys
Cleansing of wastes
Fluid intake
Red blood cell life expectancy
Blood is sensitive to malnutrition

19. 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

20. 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

21. Cutaway Side View of the Brain Showing the Hypothalamus & Cortex

22. 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

23. The Immune System Cooperation among tissues to maintain defenses
Physical barriers
Antigen
Immune defenses
White blood cells
Phagocytes
Lymphocytes (T-cells and B-cells)

24. 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

25. 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

26. The Innate Preference for Sweet Taste

27. 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

28. The Digestive System

29. 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

30. Peristaltic Wave Passing Down the Esophagus and Beyond

31. The Muscular Stomach

32. The Digestive System Chemical digestion Digestive juices Mouth Stomach
Salivary glands, stomach, pancreas, liver, and small intestine
Mouth
Saliva – starches and fat
Saliva – health of teeth
Stomach
Hydrochloric acid – protein

33. pH Values of Digestive Juice and Other Common Fluids

34. The Digestive System Chemical digestion
Intestine
Bile
Pancreatic juice
Digestive enzymes in wall of intestine
Fiber
Food combinations and digestion

35. “I Am What I Eat” Within 24 to 48 hours Mouth
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

36. “I Am What I Eat” Stomach Small intestine Large intestine
Gastric juice mixes with food
Unwinds proteins
Chyme
Small intestine
Bile from the liver
Pancreas
Large intestine

37. Typical Digestive System Transit Times

38. “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

39. Details of the Small Intestine Lining

40. “I Am What I Eat” Transport Nourishment of digestive tract
Lymph vessels
Products of fat digestion
Fat-soluble vitamins
Blood vessels
Products of carbohydrate & protein digestion
Most vitamins
Minerals
Nourishment of digestive tract

41. A Letter from Your Digestive Tract
Hiccups
Fiber and gas
Heartburn
Antacids
GERD
Ulcers

42. A Letter from Your Digestive Tract
Choking
Constipation & diarrhea
Hemorrhoids
Irritable bowel syndrome (IBS)

43. Normal Swallowing and Choking

44. First Aid for Choking

45. The Excretory System Organs involved in waste removal Kidneys
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

46. Storage Systems Eating intervals of 4-6 hours Major storage sites
Liver – carbohydrates
Glycogen
Muscles – carbohydrates
Fat cells – fat and fat-related substances
Variations in nutrient stores

47. Alcohol and Nutrition: Do the Benefits Outweigh the Risks?
Controversy 3

48. 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

49. Does Moderate Alcohol Use Benefit Health?
Influence of age
Middle-aged people
Influence of drinking patterns
Light to moderate intakes
Health benefits of wine
Science is mixed

50. What is Alcohol? Names end in –ol Act as lipid solvents Ethanol
Alcoholic beverages
Social interactions
Nonalcoholic beverages

51. What is a “Drink”? Beverage volume Proof Defining a drink
Percentage of alcohol
Defining a drink

52. Drinking Patterns Defining moderation Problem drinkers and alcoholism
Difficulties with defining
Health authority definition
Problem drinkers and alcoholism
Irrational and dangerous behaviors
Health effects
Heavy episodic drinking
Defined
Harms

53. Behaviors Typical of Moderate Drinkers and Problem Drinkers

54. 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

55. 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

56. Effects of Rising Blood Alcohol Levels on the Brain

57. Alcohol Doses and Average Blood Level Percentages

58. Blood Alcohol and Traffic Accidents

59. Alcohol Arrives in the Body
Liver processes most of the body’s alcohol
Alcohol dehydrogenase (ADH)
Acetaldehyde
Alcohol breakdown in the stomach
Women vs. men
Excretion in breath and urine
Rate of alcohol clearance

60. Alcohol Breakdown

61. Alcohol Affects the Liver
Alcohol metabolism generates damaging free radicals
Diseases and organ damage
Fatty liver
Liver fibrosis
Cirrhosis

62. The Hangover Mild form of drug withdrawal Contributors to hangovers
Congeners
Dehydration
Formaldehyde
Methanol
Sure cure for hangover

63. 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

64. 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

65. Calories in Alcoholic Beverages and Mixers