1 / 22

Chapter 24, part 3

Chapter 24, part 3. The Digestive System. Histology of the stomach. Gastric glands Parietal cells Intrinsic factor, and HCl Chief cells Pepsinogen Pyloric glands Mucous secretion containing several hormones Enteroendocrine cells G cells secrete gastrin D cells secrete somatostatin.

garyervin
Download Presentation

Chapter 24, part 3

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 24, part 3 The Digestive System

  2. Histology of the stomach • Gastric glands • Parietal cells • Intrinsic factor, and HCl • Chief cells • Pepsinogen • Pyloric glands • Mucous secretion containing several hormones • Enteroendocrine cells • G cells secrete gastrin • D cells secrete somatostatin

  3. Figure 24.13 The Stomach Lining Figure 24.13a, b

  4. Figure 24.13 The Stomach Lining Figure 24.13c, d

  5. Figure 24.14 The Secretions of Hydrochloric Acid Figure 24.14

  6. Regulation of gastric activity • Cephalic phase prepares stomach to receive ingested material • Gastric phase begins with the arrival of food in the stomach • Neural, hormonal, and local responses • Intestinal phase controls the rate of gastric emptying

  7. Figure 24.15 The Phases of Gastric Secretion Figure 24.15a

  8. Figure 24.15 The Phases of Gastric Secretion Figure 24.15b

  9. Figure 24.15 The Phases of Gastric Secretion Figure 24.15c

  10. Digestion and absorption in the stomach • Preliminary digestion of proteins • Pepsin • Permits digestion of carbohydrates • Very little absorption of nutrients • Some drugs, however, are absorbed

  11. SECTION 24-6The Small Intestine and Associated Glandular Organs

  12. Small intestine • Important digestive and absorptive functions • Secretions and buffers provided by pancreas, liver, gall bladder • Three subdivisions: • Duodenum • Jejunum • Ileum • Ileocecal sphincter • Transition between small and large intestine

  13. Figure 24.16 Regions of the Small Intestine Figure 24.16a

  14. Histology of the small intestine • Plicae • Transverse folds of the intestinal lining • Villi • Fingerlike projections of the mucosa • Lacteals • Terminal lymphatic in villus • Intestinal glands • Lined by enteroendocrine, goblet and stem cells

  15. Figure 24.17 The Intestinal Wall Figure 24.17a

  16. Figure 24.17 The Intestinal Wall Figure 24.17b, c

  17. Figure 24.17 The Intestinal Wall Figure 24.17d, e

  18. Intestinal juices • Moisten chyme • Help buffer acids • Maintain digestive material in solution

  19. Small Intestine • Duodenal glands (Brunner’s glands) • produce mucus, buffers, urogastrone • Ileum • aggregated lymphoid nodules (Peyer’s patches)

  20. Intestinal movements • Peristalsis • Segmentation • Gastroenteric reflexes • Initiated by stretch receptors in stomach • Gastroileal reflex • Triggers relaxation of ileocecal valve

  21. The pancreas • Pancreatic duct penetrates duodenal wall • Endocrine functions • Insulin and glucagons • Exocrine functions • Majority of pancreatic secretions • Pancreatic juice secreted into small intestine • Carbohydrases • Lipases • Nucleases • Proteolytic enzymes

  22. Figure 24.18 The Pancreas Figure 24.18a-c

More Related