l4: “digestion in the mouth”. question: how does the digestion of starch occur in the mouth?

L4:“Digestion in the

Mouth”

Question:How does the digestion of starch occur in the mouth?

HYPOTHESIS:If starch is digested in the mouth

Then we will seeBecause

PROCEDURE1

30 drops starch

3

30 drops DW

+

2 drops amylase

5

30 drops starch

+

2 drops amylase

2

30 drops starch

4

30 drops DW

+

2 drops amylase

6

30 drops starch

+

2 drops amylase

PROCEDURE:Stir with toothpick.Allow cups to sit for at least 5 minutes.

1. What do you think amylase is?2. What do you think amylase will do

when you mix it with the starch solution?

3. Why do you need to wait 5 minutes before you perform the tests on the starch solution and amylase mixture?

PROCEDURE:Perform a sugar test on the top row (10

drops of Benedicts in 1, 3, 5) – put in 3 different test tubes and place in water bath

Perform a starch test on the bottom row (3 drops of Lugols in 2, 4, 6)

Record results on data chart.

Data:Test type: Starch: DW &

amylase:Starch & amylase:

Sugar Test Results

1 3 5

Starch Test Results

2 4 6

Benedicts and Lugols

Benedicts (1,3,5)

+ = light green orange

- = blue

Lugols (2,4,6)

+ = dark blue/purple or black

- = yellowish brown

DATA QUESTIONS:1. For which nutrient, sugar (well 1) or starch

(well 2), did the starch solution test positive?2. For which nutrient, sugar (well 3) or starch

(well 4), did the amylase (with DW) test positive?

3. For which nutrient, sugar (well 5) or starch (well 6), did the mixture of amylase & starch solution test positive?

DATA QUESTIONS:4. Amylase is found in human

saliva. It is a certain type of chemical called an enzyme. On the basis of what amylase did in this inquiry, how would you define an enzyme?

VOCABULARY:Mechanical digestionChemical digestionAmylaseEnzyme

Vocabulary defined:

Mechanical digestion – break down food using your teeth

Chemical digestion – break down food using chemicals (ex. Amylase)

Amylase – enzyme; helps break down starch

Enzyme – protein; speeds up chemical reactions

CONCLUSION:Be sure to use complete sentences.Make the original question a statement.Was your hypothesis supported or

rejected and why?Be sure to use each vocabulary word in

your conclusion and UNDERLINE.