8. Campbell; Fig.41.12a

9. Campbell; Fig.41.12b

10. Campbell; Fig.41.12c  Highly reliant on digestive system to remain healthy  Cannot afford to store heavy materials in body for lengthy period

12. Lignin Cellulose

24. Rumen & Reticulum Abomassum Omassum Fermentation Filter True digestive stomach To intestine pH = 1 - 2 Mouth

25. Fungi Protozoa Bacteria

26. Foregut fermenters: * * Both have enlarged, multi-chambered foreguts *

27. Hindgut fermenters cecum * * Enlarged hindgut (a big S. American rodent)

28. The most primitive 蠑螈 泄殖腔 嗉囊 沙囊 Fig. 21.5 One-way digestive tracts Specialization in different regions

33. Fig. 21.17 The pancreatic and bile ducts empty into the duodenum

34. Fig. 21.20 Nitrogenous wastes

36. Fig. 21.26

37. Fig. 21.27 Osmoregulation in elasmobranchs

38. Fig. 21.31 The mammalian urinary system

40. Examples of modified incisors

42. Rumen (Punch)

43. Reticulum (Hardware Stomach or Tripe)

44. Omasum (manyplies)

47. Sheep liver fluke

48. 8.8

49. 8.9a and b

50. 8.11

51. 8.12

52. Tapeworm scolex The scolex is equipped with a combination of suckers and hooks that enable it to grip onto its host’s intestines. Hooks Suckers

53. 8.14

54. 8.15

55. 8.16 Cysticerci in human brain

56. 8.18 Internal structure of female ribbon worm (above). Nemertean with proboscis extended (right)

57. 8.19 Baseodiscus mexicanus a nemertean from the Galapagos Islands

58. 8.20 Gnathostomula jenneri

60. Anatomy of Digestive System

61. Anatomy of Digestive System

63. Anatomy of Digestive System

64. Anatomy of Digestive System

66. Structure of Cellulose Fig. 5.7 Glucose occurs in two conformations,  and  . In cellulose, every other glucose is “upside down” making it impossible for amylase (enzyme found in animals) to digest it. Very few animals have evolved the enzyme cellulase , but many microbes have this enzyme.

67. Digestive System Chapter 14 Figure 14.1 Pharynx • Passageway for food and air • Participates in swallowing Esophagus • Moves food from pharynx to stomach Salivary glands • Saliva moistens food • Bicarbonate maintains pH • Amylase digests starch • Lysozyme inhibits bacteria ACCESSORY ORGANS: Liver • Produces bile • Performs various functions associated with processing and storing nutrients Pancreas • Secretes digestive enzymes into small intestine • Secretes bicarbonate into small intestine to neutralize stomach acid Gallbladder • Stores and concentrates bile Mouth • Teeth chew food • Tongue positions and tastes food ORGANS: Appendix • No known digestive function Stomach • Stores and mixes food • Begins chemical digestion of protein by enzymes and acid • Regulates delivery to the small intestine Anus • Expels undigested material Rectum • Passageway for feces Sigmoid colon • Stores feces Large intestine • Absorbs the last of the water and nutrients • Stores waste material Small intestine • Digests proteins, fats, and carbohydrates • Absorbs most of the water and nutrients • Secretes digestive hormones and enzymes

68. Gastrointestinal (GI) Tract Wall Figure 14.2 Lumen Circular layer Longitudinal layer Lymph vessel Serosa • Connective tissue outer covering • Protects and anchors the digestive tract Mucosa • Mucous membrane layer • Lines the digestive tract Submucosa • Connective tissue layer • Contains blood vessels, lymph vessels, and nerves Muscularis • Two layers of smooth muscle • Responsible for motility of the digestive tract Vein Artery Nerve

69. Motility: Peristalsis Figure 14.3a

70. Motility: Segmentation Figure 14.3b

71. Salivary Glands Figure 14.5

72. Swallowing Figure 14.6a

73. Swallowing Figure 14.6b

74. Structure of the Stomach Wall Figure 14.7a–b

75. The Stomach Figure 14.7

76. Peristalsis Figure 14.8

77. The Wall of the Small Intestine Figure 14.9a–b

78. The Wall of the Small Intestine Figure 14.9c

79. Accessory Organs: Aid Digestion and Absorption Figure 14.10 Esophagus Liver • Produces bile (water and electrolytes, cholesterol, bile salts, lecithin, and pigments) Gallbladder • Stores and concentrates bile • Delivers bile to the duodenum via the common bile duct Pancreas • Secretes enzymes (proteases, amylase, lipase) • Produces sodium bicarbonate • Delivers these products to the duodenum via ducts Stomach Pancreatic duct Common bile duct Duodenum

80. Accessory Organs: Aid Digestion and Absorption Figure 14.11

81. Large Intestine Figure 14.12 Sigmoid colon Descending colon External anal sphincter (skeletal muscle) Anus Anal canal Rectum Internal anal sphincter (smooth muscle) Appendix Cecum Ileocecal valve Ascending colon Transverse colon Small intestine

82. Absorption of Proteins and Carbohydrates Figure 14.13

83. Absorption of Fats Figure 14.14

85. Copyright  The McGraw-Hill Companies, Inc. Permission required for reproduction or display .

99. Copyright  The McGraw-Hill Companies, Inc. Permission required for reproduction or display .

102. Goblet cells

108. Nutrients: Utilized or Stored Until Needed Figure 14.15

109. Food Guide Pyramid Figure 14.16