The Digestive System

1. What is the digestive tract? A long continuous tube with food first entering at the mouth.
2. What happens to undigested materials in the digestive tract? It exits out the anus with dead cells, bacteria and other waste .
3. Sketch the path that food takes through the digestive tract. Be sure to include the mouth, esophagus, stomach, duodenum, small intestine, appendix, large intestine rectum, and all 4 sphincters. This message is from me to me. Remember that you saw this and it was fine., Blogger just did not want to post it.
4. What is the function of the mouth in the digestion process? It brings the food into the body and breaks it down.
5. What is the term for the small mass of food that enters into the esophagus? Bolus
6. What triggers peristalsis? presence of the bolus in the esophagus.
7. What is the function of the cardiac sphincter? It closes the entrance to the stomach and prevents its contents from re-entering the esophagus.
8. What is the mucous membrane? A protective layer that lines the entire digestive tract.
9. How long is the small intestine? Over 20 feet.
10. Where does most digestion and absorption of nutrients take place? In the small intestine.
11. What increase the surface area of the small intestine? Villi
12. What is the first section of the small intestine? What is its function? The duodenum. its receptors can detect the presences of hypo- and hyper-tonic solutions, acid and chemical changes in the chyme which, via the duodenum, affect the action of the entire gastrointestinal tract.
13. Where is bile stored? In the gallbladder
14. What is segmentation? A muscle contraction that breaks up the intestinal contents and mixes them with the digestive juices.
15. When does the ileocecal sphincter open? When the amount of food in the small intestine begins to build up.
16. What is the function of the anal sphincter? Stops waste from leaving the body until you want it to.
17. What is the function of the appendix in humans? There is no function for it in humans.
18. Where does digestion begin? In the mouth
19. What is gastric juice made of? A mixture of hydrochloric acid
20. Where are enzymes released in the small intestine produced? By the pancreas or the the intestinal glands
21. What is the function of the following enzymes: amylase, lactase, maltase, sucrase, and lipase? Amylase- completes the process of hydrolyzing starch; Maltase
22. There are two ways that nutrients get into the blood stream. Describe each method. Some diffuse across the intestinal membranes and into the blood by flowing along the concetration gradient. Others are forced through the membrane against a gradient, since their concentration in the blood is alreadt greater than it is in the intestinal lumen.