Lesson 25 and 26 - Digestion
Lesson Objectives
A. Content Objective: The digestive process has a variety of steps and organs. Enzymes are the main molecules that break down polymers into monomers that can easily be absorbed. The digestion of proteins starts in the stomach and requires the maintenance of an acidic environment. The small intestine is where most digestion and absorption takes place. This requires enzymes from the pancreas and specialized cells that can absorb the monomers.
B. Language Objective: To describe the processes in the digestion and to explain how the villi maximizes absorption.
C. Syllabus Statements:
The contraction of circular and longitudinal muscle of the small intestine mixes the food with enzymes and moves it along the gut.
The pancreas secretes enzymes into the lumen of the small intestine.
Enzymes digest most macromolecules in food into monomers in the small intestine.
Villi increase the surface area of epithelium over which absorption is carried out.
Villi absorb monomers formed by digestion as well as mineral ions and vitamins.
Different methods of membrane transport are required to absorb different nutrients.
Application: Processes occurring in the small intestine that result in the digestion of starch and transport of the products of digestion to the liver.
Application: Use of dialysis tubing to model absorption of digested food in the intestine.
Skill: Production of an annotated diagram of the digestive system.
Skill: Identification of tissue layers in transverse sections of the small intestine viewed with a microscope or in a micrograph.
Activites
Activity 1 - Digestion
Watch this digestion video.
This video will help with the basics of digestion:
Activity 2 - Enzymes in Digestion
1. Create a table with the following titles and make sure you have space for at least 12 enzymes.
-Name of Enzyme, Produced by, Substrate, Products, optimum pH
2. Add the following enzymes to the table:
amylase, dextrinase, maltase, lipase, protease, lactase, phospholipase, sucrase, dipeptidase.
Activity 3 - Villi Structure and function
Instructions:
Using this document, please label the following key terms on your diagrams. You would be expected to be able to label these.
Key Terms:
Serosa, mucosa, submucosa, circular muscles, longitudinal muscles, intestinal crypts, villi, microvilli, capillaries, Tight Junctions, mitochondria, Pinocytotic Vesicles.
Activity 4 - Transport across villi
Please complete this table about the transport of molecules across the membrane of the villi
Activity 4 - Small Intestine Summary
Please create a two-minute video explaining the structure and function of the villi of the small intestine to a family member (parents, siblings, etc). I do not mind what language it is in, but you need to include a hand-drawn picture in your explanation. Please post it in Google Classroom.
Home Learning
A. Strengthen Your Skills
Small Intestine Song - Sorry....
Glucose Absorption in the Small Intestine
Absorption in the Small Intestine
Digestion in the Small Intestine
B. Expand Your Knowledge