Question

1. If you were to place an unsalted cracker on your tongue and left it there (no chewing), it would soon begin to taste sweet. Crackers have starch in them. What enzyme is likely present in your saliva, and what is the starch likely being broken down into. 2. Based on what you've learned about enzymes throughout the semester, please answer the following: A similar version of the enzyme from the previous question is also secreted in the small intestine. Why would you need to do that? In other words, why isn't the enzyme that is part of saliva enough to continue to break down food as you reach the small intestine? 3. Why was test tube P1 included in the experiment? 4. Someone tells you they think the stomach breaks down food because it's so acidic. Explain why the data from test tube P2 would contradict that statement

Answer 1

1. In our saliva, there is an enzyme called salivary amylase that digests the carbohydrates in our food. Starch is broken down into glucose, amylose and amylopectin which are responsible for the sweet taste. The major component in which starch is broken down into is maltose.

2. The enzyme of the saliva is not enough as it will get denatured in the low pH of the stomach and will not be able to continue digestion till the small intestine. If we swallow too fast then the complete digestion of food is not possible. To completely digest the carbohydrates present in the food we need another enzyme.