Digestive System Worksheet

1. What is the digestive tract? Basically a series of tubes that is used to digest food, absorb nutrients and send them into the bloodstream, and condense waste to be removed by the body.

2. What happens to undigested materials in the digestive tract? It is condensed in the large intestine and then sent into the rectum, where it waits until the need of removal.

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.
























4. What is the function of the mouth in the digestion process? To take in the food, chew it, and produce saliva to begin breaking up the material.

5. What is the term for the small mass of food that enters into the esophagus? Bolus.

6. What is the term for partially digested stomach contents? Chyme.

7. What triggers peristalsis? The presence of bolus in the esophagus.

8. What is the function of the cardiac sphincter? To keep food from re-entering the esophagus.

9. What is the mucous membrane? A layer of mucous that coats the entire digestive tract to prevent the digestive tract from digesting itself.

10. How long is the small intestine? Over 20 feet.

11. Where does most digestion and absorption of nutrients take place? In the small intestine.

12. What increase the surface area of the small intestine? Villi.

13. What is the first section of the small intestine? The duodenum. What is its function? It reacts to chemical changes of the chyme entering the small intestine and is also where the galbladder secretes the bile. It also controls the entire digestive tract.

14. Where is bile stored? In the galbladder.

15. What is segmentation? The squeezing of a tube (in this case the intestine) to further break down its contents.

16. When does the ileocecal sphincter open? When the amount of food against it builds up enough.

17. What is the function of the anal sphincter? To keep in the poo until you're ready!

18. What is the function of the appendix in humans? There isn't one.

19. Where does digestion begin? In the mouth.

20. What is gastric juice made of? Hydrocloric acid and enzymes.

21. Where are the enzymes released in the small intestine produced? Pancreas.

22. What is the function of the following enzymes: amylase, lactase, maltase, sucrase, and lipase?
Amylase - completes the process of hydrolyzing starch into the double sugar maltose.
Lactase - Breaks apart lactose.
Maltase - Breaks apart maltose.
Sucrase - Breaks apart sucrose.
Lipase - Splits fat into its components, glycerol and fatty acids.

23. There are two ways that nutrients get into the blood stream. Describe each method.
1. Energy produced by the splitting of some sugar molecules is used to help actively transport them across the membranes of the intestine and into the blood stream.

2. And passive transport, where the nutrients can go through the membrane using no energy.