Interactive - Unit 4. Lesson 6b. The digestive system

the video and study the illustration of the digestive system. Then, develop the activities I. Click on the gap, and choose the best completion. If you can't remember, go back to your booklet and review the information. The digestive system's job is to processfood. In order to use the food we eat, our body has to break the food down into smaller molecules that it can absorb; it also has to excrete wastes.The digestive process begins in the mouth. Food is partly broken down by the process of chewing and by the chemical action of salivary enzymes.After being chewed and swallowed, the food enters the oesophagus, which is a long tube that runs from the stomach to the mouth. The action of peristalsis forces the food into the stomach.In the stomach, food that is partly digested churns (mixes) and is bathed in a very strong acid. This is known as chemical digestion.The churned up food then enters the small intestines where the breakdown continues. Water and nutrients are reabsorbed into the body so that we recieve the important things we need from our food.After the small intestines comes the large intestines. Here, some of the water and electrolytes is removed from the food and reabsorbed into the body. After passing through the large intestine, most of the water is gone and the solid waste is stored in the rectum until it is excreted via the anus. II. Digestion begins in the mouth. Which of the following statement is INCORRECT? The tongue releases enzymes that breakdown food. The saliva contains enzymes. The tongue keeps the food in place in the mouth while the food is being chewed. The digestive juices can react more easily with the food when chewed. III. Where does food pass through between the mouth and the stomach? The rectum The small intestine The large intestine The esophagus IV. Our throat divides into two separate tubes: the trachea and the oesophagus. What prevents food from entering the windpipe? The epiglottis The tongue The larynx The rectum V. What happens when food reaches the stomach? Nothing. No digestion occurs in the stomach. The food moves quickly into the small intestine. Juices mix with the food and stomach muscles squeeze it. The food is completely digested and is absorbed by tiny blood vessels in the walls of the stomach. VI. Where does the partly-digested food (in liquid form) go after it leaves the stomach? The gullet The appendix The small intestine The large intestine VII. Water is aborbed in the... gall bladder large intestine small intestine stomach VIII. The absorption of nutrients (proteins, glucose, etc) is done in the large intestine liver small intestine rectum IX. Bile secreted by the liver is delivered into the... stomach large intestine pancreas small intestine