Question

name how the digestive system works to find out what you already know about the digestive system, write a word or words from the word bank to complete each definition. word bank gastric juice digestion large intestine rectum tongue appendix enzymes intestinal juice saliva villi peristalsis esophagus mechanical small intestine bile chemical salivary glands gallbladder pancreas stomach 1. is the process by which food is broken down into substances that can be used by the cells of the body. 2. in the digestive system, food undergoes two kinds of digestion. digestion occurs as the food is broken into smaller pieces. 3. mechanical digestion prepares the food for diges- tion, which is the process by which foods are chemically changed into simpler substances. 4. digestion begins as soon as food enters the mouth, where the teeth and tongue work together to physically break down the food into smaller pieces. as chewing takes place, a secretion from the softens and lubri- cates the food. 5. this secretion from the salivary glands is called. 6. saliva contains, substances that speed up chemical reactions and break down large starch molecules into smaller molecules of sugar. 7. the helps push food to the back of the mouth where it is swallowed. 8. after being swallowed, the food passes into a muscular tube called the, which connects the mouth to the stomach. 9. food in the esophagus is squeezed toward the stomach by contraction and relaxation of the muscles in the esophagus. this muscular action, known as, also helps to move food through the rest of the digestive tract.

Explanation:

1. Digestion is the process of breaking food into usable substances.
2. Mechanical digestion breaks food into smaller pieces.
3. Mechanical digestion prepares for chemical digestion (chemical change of food).
4. Salivary glands secrete to soften/lubricate food.
5. Secretion from salivary glands is saliva.
6. Saliva has enzymes (speed chemical reactions, break starch).
7. Tongue pushes food for swallowing.
8. Esophagus connects mouth to stomach.
9. Peristalsis (muscle contraction/relaxation) moves food.

Answer:

1. digestion
2. mechanical
3. chemical
4. salivary glands
5. saliva
6. enzymes
7. tongue
8. esophagus
9. peristalsis