Bio 449 Lecture 31 – Digestive Physiology III Nov. 22, 2010 Function and control of the GI tract (conclusion) Transport Carbohydrates and amino acids Fats Water recovery Defecation Terms to Know Portal system Hepatic portal vein Mass movement Internal anal sphincter External anal sphincter Readings Lectures 29-31: Chapter 21

Hepatic circulatory patterns Aorta Hepatic vein Inferior vena cava Digestive tract arteries Hepatic portal vein Hepatic artery Capillaries of liver Capillaries of digestive tract: stomach, intestines, pancreas, and spleen Liver Fig. 21-30

Large intestine Fig. 21-30 Rectum Internal anal sphincter Anus External anal sphincter Cecum Appendix Ileum Ileocecal valve Ascending colon Transverse colon Aorta Hepatic portal vein Inferior vena cava Descending colon Sigmoid colon Haustra Tenia coli Circular muscle Longitudinal layer (tenia coli) Intestinal glands Lymphoid nodule Submucosa Muscularis externa Muscularis mucosae Fig. 21-30

Anal sphincters Rectum Internal anal sphincter External anal sphincter Anus External anal sphincter Fig. 21-30

Fluid secretion and reabsorption 7.5 L from small intestine 1.4 L from large intestine 0.1 L in feces 9.0 L removed from lumen 2.0 L food and drink 1.5 L saliva (salivary glands) 0.5 L bile (liver) 2.0 L gastric secretions 1.5 L pancreatic secretions 1.5 L intestinal secretions 9.0 L Total input into lumen Absorption Excretion Fluid input into digestive system Fluid removed from digestive system Ingestion Secretion Fig. 21-1