BIOL 203 FINAL EXAM REVIEW STUDY GUIDE 2024

Digestion - breaks down food into nutrients Absorption - brings the nutrients into the cells of the small intestine for transport to other body cells path of food through the body - - mouth -esophagus -upper and lower esophageal sphincters -stomach -pyloric sphincter -small intestine -ileocecal sphincter -large intestine -past the appendix -rectum -anus ***The wavelike contractions of peristalsis and the periodic squeezing of segmentation, keeps things moving ***Along the way, secretions from the salivary glands, stomach, pancreas, liver and small intestine deliver fluids and digestive enzymes Importance of the many folds and villi of the small intestine - increase its surface area, making nutrient absorption efficient nutrients pass through the cells of the intestinal villi and enter the BLOOD if... - they are water soluble or small fat fragments nutrients pass through the cells of the intestinal villi and enter the LYMPH if... - they are fat soluble Nutrients leaving the digestive system via the BLOOD are routed directly to the _______ before being transported to the body's cells - liver Nutrients leaving the digestive system via the LYMPHATIC system bypass the ______ at first, but eventually enter the _________ via the thoracic duct, which opens into the subclavian vein - liver, vascular system bacteria - supports GI health the regulation of GI processes depends on the coordinated efforts of: - the hormonal system and the nervous system Describe the challenges associated with digesting food and the solutions offered by the human body - Describe the path food follows as it travels through the digestive system. Summarize the muscular actions that take place along the way - Name five organs that secrete digestive juices. How do the juices and enzymes facilitate digestion? - What is the name of the semiliquid, partially digested food that travels through the intestinal tract? - chyme What are the muscular contractions that propel food through the GI tract called? - peristalsis What is the main function of bile? - to emulsify fats What does the pancreas secrete in order to neutralize stomach acid in the small intestine? - bicarbonate What nutrient passes through the GI tract mostly undigested and unabsorbed? - fibre Describe the problems associated with a absorbing nutrients and the solutions offered by the small intestine - Where does absorption primarily occur - in the small intestine Describe three common processes used for absorbing nutrients? - How is blood routed through the digestive system? Which nutrients enter the bloodstream directly? Which are first absorbed into the lymph? - Where does all blood leaving the GI tract travel to first? - the liver Which nutrients leave the GI tract by way of the lymphatic system? - fats and fat-soluble vitamins Describe how the body coordinates and regulates the processes of digestion and absorption - How does the composition of the diet influence the functioning of the GI tract? - What steps can you take to help your GI tract function at its best?