Digestive Enzymes cracker lab sheet.docx - Digestive...

Digestive Enzymes – Salivary Amylase
Chemical digestion is aided by digestive enzymes from the pancreas and salivary glands. Enzymes will
catabolize or breakdown the macromolecules in the food we eat. Enzymes are specific proteins that
work on specific molecules or substrates in the body. Lipids are catabolized by lipases, proteins by
proteases, and saccharides by amylases. Enzymes speed up or catalyze reactions between substrates but
does not change itself in the reaction.
In this lab activity we will be using salivary amylase to demonstrate digestion of a carbohydrate into
glucose. Carbohydrate digestion begins in the mouth with mechanical digestion of chewing and chemical
with amylase from the salivary glands at a pH of 7.4. However, salivary amylase is denatured in the
environment of the stomach, which is a much lower pH due to hydrochloric acid.
Lab Activity
1. Get the cracker from your lab kit package and break off two squares, each approximately ½ inch
square.