Download Digestion Practice Test: KEY

Name:________________________________ DIGESTION – PRACTICE TEST Multiple Choice: Use the following diagram to answer questions 1 and 2. 1. The structure labeled X is the A. trachea. B. pharynx. C. epiglottis. D. esophagus. 2. Which structure stores bile? A. V B. W C. Y D. Z 3. Secretions from the stomach promote the digestion of A. fats. B. proteins. C. nucleic acids. D. carbohydrates. Name:________________________________ 4. Which of the following statements about insulin is correct? A. Insulin is produced by the liver. B. Insulin causes a decrease in blood sugar. C. Insulin decreases the hydrogen ion concentration in the blood. D. Insulin is secreted when fats are present in the digestive system. 5. Which of the following protects the walls of the stomach from hydrochloric acid? A. bile B. pepsin C. mucus D. bicarbonate ions 6. What structure prevents the movement of chyme from the stomach to the esophagus? A. the larynx B. the epiglottis C. the pyloric sphincter D. the cardiac sphincter 7. Gastric juices are produced by the A. intestine and contain hydrochloric acid. B. stomach and contain hydrochloric acid. C. stomach and contain sodium bicarbonate. D. intestine and contain sodium bicarbonate. 8. What two structures produce chemicals that digest proteins? A. the liver and the pancreas B. the salivary and intestinal glands C. the gastric glands and the pancreas D. the gastric glands and the gall bladder 9. Blood proteins are made in the A. liver. B. kidney. C. stomach. D. pancreas Name:________________________________ WRITTEN 1. Explain how the liver is involved in each of the following processes. digestion of fat: The liver produces bile, which is stored in the gallbladder. Bile emulsifies fats, meaning it breaks the fat droplets into smaller fat droplets. maintenance of blood glucose levels: The liver takes up glucose and stores it as glycogen. This lowers blood glucose levels OR The liver breaks down glycogen to glucose. This increases blood glucose levels. 2) Describe the process of starch being chemically digested. Salivary amylase turns starch into maltose in the mouth. In the duodenum the pancreas releases pancreatic amylase that continues to break the starch into maltose. Finally in the jejunum, maltase is secreted by intestinal crypts that break the maltose into glucose molecules. These glucose molecules are then absorbed into the capillary beds of the villi. Name:________________________________ 3) Name the function of each letter in the diagram below X: The lacteal takes up fatty acids and glycerol Y: The capillary bed takes up glucose, aa’s, and nucleotides Z: The outer (epithelia) cells of the villi contain microvilli, which increases the S.A. and allows for more absorption A: The intestinal crypt secretes intestinal juices for digestion in the small intestine 4. Describe the mechanisms involved in the digestion and absorption of fat. Fat goes in the mouth and travels down the esophagus into the stomach through the cardiac sphincter. It in not until the fat leaves the stomach, via the pyloric sphincter, and enters the duodenum that it begins to be digested. The liver produces bile that is stored in the gall bladder, this bile is then released into the duodenum. Bile emulsifies fats, breaking these droplets into small droplets (mechanical). In the jejunum intestinal juices that include lipase is released. Lipase breaks the fats (triglycerides) into fatty acids and glycerol. The fatty acids and glycerol are absorbed into the villi of the small intestine and into the lacteal (part of the lymph system). Name:________________________________ 4 1 8 7 5 6