Digestive System

1. Digestive System

2. Standards: • 4a. Describe the chemical and physical mechanisms of digestion, elimination, transportation, and absorption within the body to change food and derive energy. • Big idea(s): • Changing food to get energy involves— • Physical and chemical changes • Basic processes of digestion, elimination, transportation & absorption

3. A. Diet: 5 basic types of nutrients 1. carbohydrates 2. proteins 3. fats 4. vitamins 5. minerals OLD

4. 1. Carbohydrates – major energy source for cells • cells break down carbohydrates (glucose) to make energy (ATP) • each gram of carbohydrates you consume yields 4 Calories (the unit we use to measure energy)

5. The largest of carbs are the polysaccharides (starches, fiber, grains) which are good for energy and digestive health The smallest are the mono- and disaccharides (sweet tasting foods) which are good for short-term energy

6. Carbohydrate-rich food categories: 1. Grains like: pasta breads Subgroups (click): http://www.choosemyplate.gov/food-groups/grains.html Key consumer message: Make at least half of your grains whole grains.

7. Carbohydrate-rich food categories: 2. Fruits, like… http://www.choosemyplate.gov/food-groups/fruits.html Key consumer message: Make half your plate fruits & vegetables.

8. 3. Vegetables: can be organized into 5 subgroups (click)— • Dark green, like… • Starchy, like… • Red & orange, like… • Beans & peas, like… • other, like…

9. Key consumer message: Make half your plate fruits & vegetables.

10. 2. Protein rich foods include: fish eggs beans nuts meat milk cheese

11. when you ingest proteins, your digestive system breaks them down into smaller polypeptides or dipeptides, then into units called amino acids • your cells need these amino acids to produce muscles, bones, enzymes, and hormones

12. Your body requires 20 different amino acids

13. 8 of these amino acids must be obtained in your diet • as long as you have these 8 amino acids, your body can manufacture the other 12 Since these 8 amino acids are so vital they have become known as the essential amino acids

14. Fish, meat, milk, and eggs are called complete proteins because they contain all 8 essential amino acids

15. Proteins, such as beans, are called incomplete (they lack 1 or more of the 8 essential amino acids)

16. your cells can break down proteins to produce energy (ATP), but only if they run out of carbohydrates • 1 gram of protein yields 4 Calories • avg person needs 6 oz. per day

17. Key consumer message (click): Select a variety of protein foods to improve nutrient intake and health benefits, including at least 8 ounces of cooked seafood per week

18. ** Dairy ** (click) Key consumer message: Switch to fat-free or low-fat (1%) milk. Calcium-fortified foods and beverages such as cereals, orange juice, or rice or almond beverages may provide calcium, but may not provide the other nutrients found in dairy products.

19. 3. Fats are required by your body to build cell membranes, to insulate nerve cells and to allow your body to absorb fat-soluble vitamins (A, D, E, and K) from the foods you eat

20. fats can also be used by your cells to produce energy (ATP), but only if you run out of carbohydrates • fats yield the greatest amount of energy – 9 Calories/gram • ** if you burn the calories!**

21. fats are digested into triglycerides, fatty acids, cholesterol • LDLs transport of lipids from liver to body cells • HDLs transport of lipids from body cells to liver

22. Fat rich foods include (click): whole milk, meat, butter, oils, fried foods, and chips Oils are NOT a food group, but they provide essential nutrients.

23. What are my allowances? (click) Key consumer message: Substitute oils for solid fats; be aware of the oils & fats in the foods you already eat.

24. 4. Vitamins are essential organic substances that are required in small amounts for normal growth and activity There are 2 major types of vitamins: a. Fat-soluble b. Water-soluble

25. Fat-soluble vitamins include vitamins A, D, E, and K Vitamin A is needed for good vision

26. too little vitamin A: • night blindness • infections of the urinary and digestive tracts

27. Vitamin D: • For strong bones and teeth

28. Too little vitamin D: • bone deformities, • bad teeth; • poor muscle tone

29. Vitamin E is needed to protect cell membranes from damage

30. too little vitamin E: • Anemia • nerve tissue damage (infants)

31. Vitamin K is needed for blood to clot

32. too little vitamin K: • increases the time it takes for blood to clot

33. Excess intake of any of the fat-soluble vitamins can be harmful because you store excesses of these of these vitamins in your body rather than excrete them

34. Overdoses of vitamin A: • enlargement of your liver & spleen • blurred vision • hair loss

35. Overdoses of vitamin D: • calcium deposited in your soft tissues (kidney stones) • high blood pressure

36. b. Water-soluble vitamins include vitamin C and the B vitamins (B1, B2, B3, and B12) • Vitamin C is needed for: • proper wound healing • healthy teeth and gums

37. too little C: • bleeding gums • loose teeth • slow wound healing

38. Vitamin B1 (thiamine) is needed for: • proper nerve & heart function • carbohydrates to be broken down

39. too little B1: • digestive problems (beriberi) • impairs sense of touch

40. Vitamin B2 (riboflavin) is needed for: • healthy skin • tissue repair • carbohydrates to be broken down

41. too little B2: • blurred vision • cataracts • cracking of the skin

42. Vitamin B3 (niacin) is needed for: • healthy skin • carbohydrates to be broken down

43. too little B3: • mental disorders • diarrhea • dermatitis of eyes, nose, and mouth

44. Vitamin B12 is needed for: • production of RBCs

45. too little B12: • anemia

46. Massive doses of water-soluble vitamins can be hazardous to your health • Excess vitamin C can cause: • kidney stones • blood clots

47. Excess niacin (B3): • liver damage • gout (uric acid crystals deposited in joints – extremely painful)

48. 5. Minerals are trace elements required by your body Some of the most important minerals you require are: iodine cobalt zinc manganese

49. Iodine is needed for you to make thyroid hormone • too little iodine causes hypothyroidism which causes stunted growth and retardation in children

50. in adults, hypothyroidism causes lack of energy, dry skin, and weight gain