Figure 22.2 Gastrointestinal tract activities. Ingestion Food Mechanical breakdown Pharynx Esophagus Chewing (mouth) Churning (stomach) Propulsion Segmentation (small intestine) • Swallowing (oropharynx) • Peristalsis (esophagus, stomach, small intestine, large intestine) Digestion Stomach Absorption Lymph vessel Small intestine Blood vessel Large intestine Mainly H2O Feces Anus Defecation © 2014 Pearson Education, Inc.

Figure 22.3a Peristalsis and segmentation. From mouth Peristalsis: Adjacent segments of alimentary tract organs alternately contract and relax, moving food along the tract distally. © 2014 Pearson Education, Inc.

Figure 22.3b Peristalsis and segmentation. Segmentation: Nonadjacent segments of alimentary tract organs alternately contract and relax, moving food forward then backward. Food mixing and slow food propulsion occur. © 2014 Pearson Education, Inc.

Figure 22.5a The peritoneum and the peritoneal cavity. Abdominopelvic cavity Vertebra Dorsal mesentery Parietal peritoneum Ventral mesentery Visceral peritoneum Peritoneal cavity Alimentary canal organ Liver Two schematic cross sections of abdominal cavity illustrate the peritoneums and mesenteries. © 2014 Pearson Education, Inc.

Figure 18.24a Arteries of the abdomen. Diaphragm Abdominal aorta L. gastric artery Inferior phrenic arteries R. gastric artery Common hepatic artery Hepatic artery proper L Celiac trunk Gastro- duodenal artery Splenic artery R R. gastroepiploic artery Middle suprarenal arteries L. gastroepiploic artery Intestinal arteries Middle colic artery Superior mesenteric artery R. colic artery Renal arteries Ileocolic artery Gonadal arteries Sigmoidal arteries Inferior mesenteric artery L. colic artery Superior rectal artery Lumbar arteries Median sacral artery Common iliac arteries © 2014 Pearson Education, Inc. Schematic flowchart.

Figure 18.29a Veins of the abdomen. Inferior vena cava Inferior phrenic veins Cystic vein Hepatic veins Hepatic portal system Hepatic portal vein Superior mesenteric vein Splenic vein Suprarenal veins Inferior mesenteric vein Renal veins Gonadal veins Lumbar veins R. ascending lumbar vein L. ascending lumbar vein Common iliac veins External iliac vein Internal iliac veins © 2014 Pearson Education, Inc. Schematic flowchart.

Figure 22.6 Basic structure of the alimentary canal. Intrinsic nerve plexuses Myenteric nerve plexus Submucosal nerve plexus Glands in submucosa Mucosa Epithelium Lamina propria Muscularis mucosae Submucosa Muscularis externa Longitudinal muscle Circular muscle Serosa Epithelium (mesothelium) Nerve Connective tissue Artery Gland in mucosa Lumen Vein Duct of gland outside alimentary canal Mucosa-associated lymphoid tissue Mesentery Lymphatic vessel © 2014 Pearson Education, Inc.

Figure 19.2a The lymphatic system. Regional lymph nodes: Internal jugular vein Entrance of right lymphatic duct into vein Cervical nodes Entrance of thoracic duct into vein Axillary nodes Thoracic duct Cisterna chyli Aorta Inguinal nodes Collecting lymphatic vessels Drained by the right lymphatic duct Drained by the thoracic duct General distribution of collecting lymphatic vessels and regional lymph nodes. © 2014 Pearson Education, Inc.

Figure 22.12a Microscopic structure of the esophagus. Mucosa (stratified squamous epithelium) Submucosa (areolar connective tissue) Lumen Muscularis externa • Circular layer • Longitudinal layer Adventitia (fibrous connective tissue) © 2014 Pearson Education, Inc.

Figure 22.7b Anatomy of the oral cavity (mouth). Upper lip Gingivae (gums) Superior labial frenulum Palatine raphe Palatoglossal arch Hard palate Palatopharyngeal arch Soft palate Uvula Palatine tonsil Posterior wall of oropharynx Tongue Sublingual fold with openings of sublingual ducts Lingual frenulum Opening of Submandibular duct Gingivae (gums) Oral vestibule Inferior labial frenulum Lower lip © 2014 Pearson Education, Inc. Anterior view

Figure 22.9 The salivary glands. Tongue Teeth Parotid gland Ducts of sublingual gland Parotid duct Masseter muscle Frenulum of tongue Body of mandible (cut) Sublingual gland Posterior belly of digastric muscle Mylohyoid muscle (cut) Submandibular duct Anterior belly of digastric muscle Submandibular gland Mucous cells Serous cells forming demilunes © 2014 Pearson Education, Inc.

Enamel Dentin Crown Dentinal tubules Pulp cavity (contains Figure 22.11 Longitudinal section of a canine tooth within its bony socket (alveolus). Enamel Dentin Crown Dentinal tubules Pulp cavity (contains blood vessels and nerves) Neck Gingival sulcus Gingiva (gum) Cement Root canal Root Periodontal ligament Apical foramen © 2014 Pearson Education, Inc. Bone

Figure 22.7a Anatomy of the oral cavity (mouth). Soft palate Palatoglossal arch Uvula Hard palate Oral cavity Palatine tonsil Tongue Oropharynx Lingual tonsil Epiglottis Hyoid bone Laryngopharynx Esophagus Trachea © 2014 Pearson Education, Inc. Sagittal section of the oral cavity and pharynx

Figure 22.13 Deglutition (swallowing). Bolus of food Tongue Uvula Pharynx Bolus Epiglottis Epiglottis Glottis Trachea Upper esophageal sphincter Bolus Esophagus During the buccal phase, the upper esophageal sphincter is contracted. The tongue presses against the hard palate, forcing the food bolus into the oropharynx. 1 The pharyngeal-esophageal phase begins as the uvula and larynx rise to prevent food from entering respiratory passageways. The tongue blocks off the mouth. The upper esophageal sphincter relaxes, allowing food to enter the esophagus. 2 The constrictor muscles of the pharynx contract, forcing food into the esophagus inferiorly. The upper esophageal sphincter contracts (closes) after food enters. 3 Relaxed muscles Peristalsis moves food through the esophagus to the stomach. 4 The gastroesophageal sphincter surrounding the cardial oriface opens, and food enters the stomach. 5 Relaxed muscles Circular muscles contract Bolus of food Longitudinal muscles contract Circular muscles contract Gastroesophageal sphincter closed Gastroesophageal sphincter opens Stomach © 2014 Pearson Education, Inc.

Figure 22.13 Deglutition (swallowing). (4 of 5) Relaxed muscles Peristalsis moves food through the esophagus to the stomach. 4 Circular muscles contract Bolus of food Longitudinal muscles contract Gastroesophageal sphincter closed Stomach © 2014 Pearson Education, Inc.

Figure 22.13 Deglutition (swallowing). (5 of 5) The gastroesophageal sphincter surrounding the cardial oriface opens, and food enters the stomach. 5 Relaxed muscles Circular muscles contract Gastroesophageal sphincter opens © 2014 Pearson Education, Inc.

Figure 22.14a Anatomy of the stomach. Cardia Fundus Esophagus Muscularis externa Serosa Longitudinal layer Circular layer Oblique layer Body Lumen Lesser curvature Rugae of mucosa Greater curvature Pyloric sphincter (valve) at pylorus Pyloric canal Pyloric antrum Duodenum © 2014 Pearson Education, Inc.

Figure 22.15b Microscopic anatomy of the stomach. Gastric pits Surface epithelium (mucous cells) Gastric pit Mucous neck cells Parietal cell Gastric gland Chief cell Enteroendocrine cell Enlarged view of gastric pits and gastric glands © 2014 Pearson Education, Inc.

Vein carrying blood to hepatic portal vessel Muscle layers Lumen Figure 22.22a Structural modifications of the small intestine that increase its surface area for digestion and absorption. Vein carrying blood to hepatic portal vessel Muscle layers Lumen Circular folds Villi © 2014 Pearson Education, Inc.

Microvilli (brush border) Absorptive cells Lacteal Villus Goblet cell Figure 22.22b Structural modifications of the small intestine that increase its surface area for digestion and absorption. Microvilli (brush border) Absorptive cells Lacteal Villus Goblet cell Blood capillaries Mucosa- associated lymphoid tissue Intestinal crypt Enteroendocrine cells Venule Muscularis mucosae Lymphatic vessel Duodenal gland Submucosa © 2014 Pearson Education, Inc.

Figure 22.29a Gross anatomy of the large intestine. Left colic (splenic) flexure Transverse mesocolon Right colic (hepatic) flexure Epiploic appendages Transverse colon Superior mesenteric artery Descending colon Haustrum Ascending colon IIeum Cut edge of mesentery IIeocecal valve Tenia coli Sigmoid colon Cecum Appendix Rectum Anal canal External anal sphincter © 2014 Pearson Education, Inc.

Figure 22.30c Mesenteries of the abdominal digestive organs. Greater omentum Transverse colon Transverse mesocolon Descending colon Jejunum Mesentery Sigmoid mesocolon Sigmoid colon Ileum © 2014 Pearson Education, Inc.