The Digestive System What body system has the function of breaking down food for absorption  into the blood?

Chemical / Mechanical Digestion Cracker Lab Name: __________________________ Class Period: ______________ Date: ____ / ____ / ______

What are some ways a cracker can be broken down by the body in order for its nutrition to be absorbed into the body? Brainstorm ideas below..

Cracker Lab 1/4 after 30 seconds: Cracker Lab 1/2 after 30 seconds: 1. Each student takes 1/4 saltine cracker and places it on the tongue in the mouth for 30 seconds. 2. Students record their observations after 30 seconds. 3. Each student takes 1/2 cracker and chews for 30 seconds then records their observations below 1/4 after 30 seconds: Cracker Lab 1/2 after 30 seconds:

After reading p. 465 students classify which activity provided evidence for physical and chemical change when food is in the mouth below. Physical/Mechanical Digestion of cracker: Chemical Digestion of cracker :

5.. Explain what peristalsis is: (see textbook) 6. Watch Class Demo of Peristalsis with demonstration of a ball squeezed down a tube sock. Record what you observed.

7. Chew up ½ of a Saltine Cracker and as you swallow the cracker put your hand against your throat and record what you observe/feel (think about the sock demo) 8. Using what you learned from this lab, textbook and digestive system notes/foldable ,students will classify the type of changes in the stomach, small intestine and large intestine.(finish foldable)

Mechanical Digestion Chemical Digestion Students complete Venn diagram to compare and contrast the evidence of mechanical and chemical changes in the digestive system Mechanical Digestion Chemical Digestion Both

front of foldable large intestine stomach small intestine Digestion After reading p. 464-468, students classify the type of changes in the stomach, small intestine and large intestine. front of foldable large intestine stomach small intestine Digestion Physical / Mechanical Physical / Mechanical Physical / Mechanical Physical / Mechanical Inside of Foldable Chemical Chemical Chemical Chemical

into chemical substances that can be absorbed and assimilated. Inside of Foldable Physical / Mechanical Physical / Mechanical Physical / Mechanical Physical / Mechanical Peristalsis slows down Muscles in the rectum release the semisolid waste from the body Peristalsis continues to move and mix the chyme Muscles in the stomach grind food into smaller pieces Digestive system process where food is broken down through chewing, mixing and churning. Chemical Chemical Chemical Chemical Gastric juice and hydrochloric acid made in stomach break apart large protein molecules Excess water is absorbed from the chyme Where most chemical digestion occurs: bile breaks down fat particles. Carbohydrates, proteins, and fats are broken down from bile. the act or process of converting food into chemical substances that can be absorbed and assimilated.

Students create a Venn diagram to compare and contrast the evidence of physical and chemical changes in the digestive system