1. What do all these have in common?
ants rattlesnake termites
sea urchin turtle cow cod
pigs feet monkey brains squid
sheep eyeballs snails octopus seaweed worms

10. Food Food – contains nutrients
Nutrients are substances in foods that the human body can digest, absorb, and use for its metabolism.

11. Roughage (also called fiber) is indigestible material in foods.
Humans are heterotrophic and therefore, must ingest food.
Food includes nutrients and roughage (fiber).
Roughage (also called fiber) is indigestible material in foods.

12. carbohydrates, proteins, lipids, minerals, vitamins, and water.
Nutrients
carbohydrates, proteins, lipids, minerals, vitamins, and water.

13. III‑1. Human Nutrition
Nutrition includes those activities by which organisms obtain and process nutrients needed for energy, growth, repair and regulation.

14. Carbohydrates, lipids, and proteins require digestion.
Vitamins, minerals, and water are small molecules and can be absorbed without digestion.
Carbohydrates, lipids, and proteins require digestion.

15. Nutritional requirements vary with an individual's age, sex and activities.

16. How does food become feces?
food
feces

17. Digestion - the process of breaking food down into a smaller, simpler form, so it can be used by the cell(s) of an organism

20. Place these in order from smallest to largest (from simple to most complex)
Organ systems
Cells
Tissues
Organs

21. Cells
Tissues
Organs
Organ systems
Simple
Complex

22. Levels of Organization in the Human Body

23. Salivary glands
epiglottis
mouth
esophagus
tongue
liver
stomach
pancreas
Small intestine
Large intestine
appendix
anus
rectum

24. liver
stomach
pancreas
Gall bladder

25. The human digestive system consists of a continuous "one‑way" tube and the assisting accessory organs.

26. How is food processed in the mouth?

27. Oral Cavity

28. 1. Oral Cavity (mouth)
Ingestion of food occurs through the mouth (oral) cavity which contains the teeth, tongue, and the openings from the salivary glands.

29. canines
incisors
rip, grip, tear food
cut (bite) food

30. incisors canines premolars molars
grind, crush food
crush food

31. What is the function of the teeth?

33. The teeth function in the mechanical breakdown of food which serves to increase the surface area of the food for enzyme action.

36. plaque

37. What are the functions of the tongue?

38. Functions of the Tongue
pushes food around mouth and between teeth
mixes food with saliva
tastes the food - mmmm!

39. Functions of the Tongue
forms mass of food for swallowing
pushes food to the back of throat (pharynx) for swallowing

41. What are those bumps on her tongue?

44. What is the tongue made of?

45. Tongue
composed of skeletal muscle with an outer layer of mucous membrane

46. Taste Zones
Bitter
Sour
Salt
Sweet

47. WRONG!

48. Salivary Glands

49. The chemical digestion of carbohydrates begins here.
The salivary glands secrete saliva which contains the enzyme amylase which digests starch into disaccharides.

50. Functions of Saliva
lubricates food
contains lysozyme
contains salivary amylase

51. This happens later on! (Not in the mouth)
disaccharide
monosaccharide

52. Composition of Saliva
95% water
mucus
salivary amylase
lysozyme

56. uvula ?

58. Swallowing animation http://www.youtube.com/watch?v=Yg_kAqBlp9Y
Good for review of entire dig. system

59. How does food get to the stomach even if you’re upside down?

60. Peristalsis
The wavelike muscular contractions that push food through the digestive tube

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

62. How is the action of peristalsis like surfing a wave?

63. Peristalsis

68. Endoscope

71. CHEW BEFORE YOU SWALLOW!

72. As a result of swallowing, food moves into the esophagus.
This begins the peristaltic action of the esophagus which moves the food to the stomach and through the GI tract.

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

75. stomach

76. Inside the Stomach

77. 1. Stomach
The stomach is a muscular organ in which food is temporarily stored, liquefied to chyme, and where protein digestion begins.
Its lining contains gastric glands which secrete enzymes and hydrochloric acid.

78. Stomach
muscular organ
stores food
mechanical digestion

79. Stomach
chemical digestion
gastric juice
pepsin and HCl
chemically digests protein

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

81. Chief cells: secrete pepsin, a proteolytic enzyme
G cells: secrete the hormone gastrin

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

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

84. 1) The chemical digestion of which nutrient begins in the stomach?
2) The _____ glands secrete _____ which contains the enzyme _______which digests starch into _______________.

85. Hydrochloric acid provides an optimum pH for the hydrolytic activity of gastric protease.
Under the influence of this enzyme, proteins are digested into polypeptides and dipeptides (amino aicds).

86. 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

87. A Gastric Ulcer

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

90. Bacteria cause ulcers

92. The Stomach

93. Mucous cells: secrete an alkaline mucus that protects the epithelium against shear stress and acid
Parietal cells: secrete hydrochloric acid!
Chief cells: secrete pepsin, a proteolytic enzyme
G cells: secrete the hormone gastrin

94. 1) The chemical digestion of which nutrient begins in the stomach?
2) The _____ glands secrete _____ which contains the enzyme _______which digests starch into _______________.

95. Hydrochloric acid provides an optimum pH for the hydrolytic activity of gastric protease.
Under the influence of this enzyme, proteins are digested into polypeptides and dipeptides (amino aicds).

96. 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.

98. Small intestine

99. * The secretion from the gall bladder is bile.
Accessory structures, the gall bladder and pancreas, empty their secretions into the small intestine.
* The secretion from the gall bladder is bile.
Bile is produced in the liver and stored in the gall bladder.

101. liver
gall bladder

102. liver
gall bladder
pancreas

103. bile
fat
fat

104. emulsification increases the surface area of fats for subsequent chemical action.

105. Bile is not an enzyme, but a chemical that emulsifies (physically break apart) fat which serves to increase the surface area of fats for subsequent chemical action.

106. pancreas

107. 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.

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

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

110. esophagus
liver
Gall bladder
Small intestine
rectum

111. villi

112. Why does the small intestine have this structure?
microvilli
Why does the small intestine have this structure?
(folds, villi, microvilli)

113. 3 2 1
1 –intestinal fold
2 – villi
3 – microvilli

114. Surface area of the small intestine

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

117.  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.

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

119. Villus (small intestine)
Lacteal
Blood capillaries

121. Villus (small intestine)
Lacteal
Blood capillaries

122. villi

123. 2) What are the three enzymes secreted by the pancreas?
1) The gall bladder and pancreas secrete _____and _____ into the small intestine for chemical digestion.
2) What are the three enzymes secreted by the pancreas?

124. 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.

125. From there, they are available for distribution by the blood.

126. 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.

127. 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.

128. 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

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

135. B. Mechanism for Chemical Digestion
Hydrolysis is the splitting of large, insoluble molecules into small, soluble molecules with the addition of water.
In organisms, this process is regulated by hydrolytic enzymes and is illustrated by the following:

136. 3 fatty acids + 1 glycerol maltose + water
maltase
maltose + water
glucose + glucose
amino acid + amino acid + amino acid
protease
Proteins + water
3 fatty acids + 1 glycerol
lipase
lipids + water

137. C. Some 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.

138. Constipation is a condition in which the large intestine is emptied with difficulty.
Too much water is reabsorbed due to sluggish peristaltic movement and the solid waste hardens.

139. Diarrhea is a gastrointestinal disturbance characterized by decreased water absorption and increased peristaltic activity of the large intestine.
This results in increased, multiple, watery feces. This condition may result severe dehydration especially in infants.

140. What is this?

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

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

144. Gallstones

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

146. Gallstones

147. Place these in the correct order
Ingestion
Digestion
Peristalsis
More Digestion
Absorption
Egestion
Peristalsis
Egestion
Ingestion
Digestion
More Digestion
Absorption

148. Design a controlled experiment to test the effect of pepsin concentration on the digestion of egg white
Design an experiment to test the effect of substrate concentration on the activity of pepsin
Design an experiment to find the optimum pH for the activity of pepsin

149. Design an experiment to find the optimum pH for the activity of pepsin
HCL pepsin pepsin water
HCL
1 capillary tube 1 capillary tube 1 capillary tube 1 capillary tube

150. Design an experiment to test the effect of substrate concentration on the activity of pepsin
pepsin pepsin pepsin water
HCL HCL HCL HCL
5 g protein g protein g protein g protein

151. Design a controlled experiment to test the effect of pepsin concentration on the digestion of egg white
10 ml pepsin ml pepsin ml pepsin ml water
10 ml HCL 10 ml HCL ml HCL ml HCL
1 capillary tube 1 capillary tube 1 capillary tube 1 capillary tube
with egg white