3. vomiting http://www.youtube.com/watch?v=Ub58JoML_3Y

4. Is vomiting peristalsis?
No, it’s
reverse peristalsis

5. Peristalsis http://www.youtube.com/watch?v=YH3U_SLp9G0&feature=related

9. Inside the Stomach

10. The Stomach

11. - stores food (muscle relaxes)
Stomach
muscular organ
- stores food (muscle relaxes)
- mechanical digestion muscular contractions churn food

12. Stomach
- chemical digestion
gastric juice
pepsin and HCl
enzyme that chemically digests protein to dipeptides

14. Levels of Organization in the Human Body

15. Tissues in the stomach Muscle Produce pepsin Produce HCl Produce mucus
= what life process?
Muscle
Produce pepsin
synthesis
Produce HCl
Produce mucus
Produce gastrin (hormone that stimulates production of HCl)

16. Mucous cells: secrete a basic mucus that protects the epithelium against shear stress and acid
Parietal cells: secrete HCl

17. Chief cells: secrete pepsin, an enzyme that breaks down proteins
G cells: secrete the hormone gastrin

18. HCl in Stomach Denatures proteins Activates pepsin
Kills bacteria; other microorganisms
Dissolves minerals

19. How does the denaturation of proteins by HCL affect chemical digestion?
Denaturation of proteins by HCL exposes more surface area to enzymes, increasing the efficiency of digestion

20. - polypeptides (several amino acids in a chain)
Hydrochloric acid provides an optimum pH for the activity of gastric protease (pepsin).
Pepsin breaks down proteins to:
- polypeptides (several amino acids in a chain)
- dipeptides (2 amino acids attached).

21. Stomach Mucosa Tissue that produces mucus
Mucus - a viscous fluid consisting of glycoproteins
Mucus protects stomach lining from acidity of HCl

22. Acid reflux - acid from stomach backs up into esophagus
What is heartburn?
Acid reflux - acid from stomach backs up into esophagus

23. Cow stomach research Holy Cow!

24. 2. unchewed food goes to RUMEN and RETICULUM
HOW COW DIGESTS:
1. cow swallows food
2. unchewed food goes to RUMEN and RETICULUM
3. cow stores food in RUMEN and RETICULUM
4. cow is now tired and rests
5. when she is hungry gain she will cough up some unchewed food (called cud!)
6. it will chew it completely and swallow it again
7.the cud goes to OMASUM and  ABOMASUM
8.in  OMASUM and  ABOMASUM food is fully digested

27. A Gastric Ulcer

28. Ulcer
open sore in the mucus membrane resulting from localized breakdown of tissues

29. Bacteria cause ulcers

30. 2) The chemical digestion of which nutrient begins in the stomach?
1) The _____ glands secrete _____ which contains the enzyme ____________ which digests starch into _______________.
salivary
saliva
Salivary amylase
dissacharides
2) The chemical digestion of which nutrient begins in the stomach?
protein

31. Small intestine

33. Partially digested, liquefied food enters the small intestine.
The small intestine is a long, convoluted tube in which the major portion of food is digested.
Partially digested, liquefied food enters the small intestine.

34. What are accessories?

35. liver 1
gall bladder 2
pancreas 3

36. Bile is produced in the liver and stored in the gall bladder.
Accessory organs, the gall bladder and pancreas, empty their secretions into the small intestine.
Bile is produced in the liver and stored in the gall bladder.

37. Bile is not an enzyme, but a chemical that emulsifies (physically break apart) fat

38. How does this affect the chemical digestion of fat?
bile
fat
fat

39. emulsification increases the surface area of fats for more efficient chemical digestion

40. Chemical Digestion
The pancreas secretes several enzymes including intestinal protease, lipase, and amylase.
Intestinal glands that line the intestinal wall secrete protease, lipase, and maltase.

41. Twenty amino acids are necessary for body maintenance and repair.
Amino acids are temporarily stored and distributed to the cells as needed for protein synthesis.
Twenty amino acids are necessary for body maintenance and repair.

42. * The chemical digestion of proteins, lipids, and carbohydrates is completed in the small intestine.

43. What are the end products of digestion?
Nutrient End - Products
Proteins
Lipids
Carbohydrates
Amino acids
Fatty acids and glycerol
Simple Sugars

44. How do the end products of digestion get to our cells?

45. Absorption The passage of the end products of digestion into the blood
The process by which usable materials are taken into an organism
The passage of materials across a cell membrane into the cell

46. esophagus
liver
Gall bladder
Small intestine
rectum

47. villi

48. microvilli

50. Lacteal (small lymph vessel)
Capillary
(tiny blood vessel)
microvilli

51. Capillaries and small lymphatic vessels, lacteals, extend into the villi.

52. Why does the small intestine have this structure?3 2 1{
Why does the small intestine have this structure?
(folds, villi, microvilli)
1 –intestinal fold
2 – villi
3 – microvilli

53.  Absorption In the Small Intestine
The lining of the small intestine contains numerous villi (small fingerlike projections) which increase the surface area of the small intestine to improve absorption.

54. Surface area of the small intestine

55. overview till stomach http://www. youtube. com/watch
Villi - freezes towards the end
villi

57. Fatty acids and glycerol are absorbed through the villi into the lacteals and are transported in the lymph.
Monosaccharides and amino acids are absorbed through the villi and enter the capillaries to be transported to the liver where they are temporarily stored.

58. Functions of the Liver Absorbs and stores nutrients Produces bile
Detoxifies poisons in the blood
Removes waste products, old RBCs from blood

59. The breakdown of glycogen releases glucose for transport.
Glucose is temporarily stored as the polysaccharide glycogen (animal sugar) in the liver.
The breakdown of glycogen releases glucose for transport.

60. What are two major functions of the small intestine?
Digestion and Absorption

62. 2) What are the three enzymes secreted by the pancreas?
1) The gall bladder releases _____ and the pancreas secretes _____ into the small intestine for chemical digestion.
bile
enzymes
2) What are the three enzymes secreted by the pancreas?
Protease, lipase, amylase

63. Chyme is acidic. Why doesn’t chyme cause ulcers in the small intestine?
The pancreas produces sodium bicarbonate which neutralizes the acidity of chyme in the small intestine. It also creates a basic pH for the optimal activity of pancreatic and intestinal enzymes

64. Diarrhea http://www.youtube.com/watch?v=ln_crYIBw00&feature=related

66. In one day your body makes:
1 LITER OF SALIVA
1-3 LITERS OF GASTRIC JUICE
1-2 LITERS OF PANCREATIC JUICE
2-3 LITERS OF INTESTINAL JUICE

67. Functions of the Large Intestine
Reabsorbs water from food mass
Absorbs vitamins
Contains bacteria which:
make vitamin K
digest organic substances
compete with dangerous bacteria in food
Elimination (egestion) of undigested waste

68. What happens when water is not reabsorbed by the large intestine?

70. Diarrhea intestinal disturbance
increased peristaltic activity of the large intestine
decreased water absorption
results in increased, multiple, watery feces; may result severe dehydration especially in infants.

71. What happens when too much water reabsorbed by the large intestine?

72. Constipation

73. Constipation sluggish peristaltic movement
too much water is reabsorbed
the solid waste hardens
large intestine is emptied with difficulty

74. 5. Large Intestine
Undigested food and water enter the large intestine where excess water is absorbed as needed.
During egestion, strong peristaltic action forces feces out through the anus.

75. Feces
Bacteria (50%)
Cellulose
Bile
Mucous
Dead cells

76. What is this?
The appendix

77. Function of Appendix? “second stomach” for digestion of plant matter
houses a “backup supply” of good intestinal bacteria

78. What is this?

79. Appendicitis is an inflammation of the appendix due to infection.

81. Other Malfunctions of the Digestive System
Ulcers are open sores in the interior wall of the digestive tract, most often in the stomach or the upper portion of the small intestine.
The acid in gastric juice irritates the sores and causes pain or discomfort.

83. Colon Cancer

84. Endoscope

86. Colorectal Cancer SEER Incidence Rates. by Race and Ethnicity, U. S

87. Colorectal Cancer U.S. Death Rates* by Race and Ethnicity, 1975–2005

89. Colon cleansing

90. Gallstones

91. Gallstones

92. Gallstones are an accumulation of hardened cholesterol and/or deposits in the gall bladder.

96. liver

97. Enjoy Your
Lunch!

98. Human digestion (vocabulary)
nutrients
digestion
absorption
fiber
anus
pharynx
esophagus
large intestine
small intestine
saliva
salivary glands
stomach
rectum
liver
pancreas
Peristalsis
chyme
villi

99. pancreas

101. liver
gall bladder

102. These are called essential amino acids.
Although humans can convert one amino acid into another, eight cannot be synthesized and must be consumed as part of the diet.
These are called essential amino acids.

104. Cholesterol
Bile Acid

106. (left) and stomach lining (right)
Normal esophagus
(left) and stomach lining (right)
Esophageal cancer (stomach lining on left)