Enzyme Lab

Presentation

We Chose to do Our Experiment on How

Effective the Enzyme Sucrase is at Producing Glucose When Kept at Different Temperatures

Background Info• Sucrase is an enzyme which helps in the digestion of

food. Digestive enzymes are in charge of breaking down food, allowing for the proper absorption of nutrients.

• Sucrase enzymes are secreted by the tips of the villi of the epithelium

• Sucrase fits perfectly into the bond between the glucose and fructose molecules that make up sucrose

How Does it Work?• Sucrase works by bringing about a chemical

reaction in sucrose that divides it into glucose and fructose

• Sucrase enzymes occur naturally in the human body. However, eating poorly, natural aging, taking certain medications, and pre-existing conditions of intestinal problems may lead to a reduction in the amount of sucrase your body produces.

Procedure1. First we got 16 test tubes and put them in a test tube rack2.We put 3 mL of sucrose solution into each test tube3.We put 0.5 grams of yeast into 12 of the test tubes. The other 4 test

tubes will serve as the control so will not contain any yeast4. Then we separated the test tubes into four groups. Each group had 3

test tubes containing sucrose solution and yeast and 1 test tube containing just sucrose solution

5.We left the first group of test tubes on our desk at room temperature (about 20°C). We put the second group into an incubator ( at 37°C). We put the third group in an ice bath ( about -1°C). And we put the fourth group in a boiling water bath ( about 100°C)

6.Then we left the test tubes for 15min.7.After 15min. was up we brought all the test tubes back to our desk

and tested them all for glucose with glucose test strips.8.Finally we recorded our results

Variables• Independent Variable (is the one that is changed) =

Temperature: Room Temperature (20°C), Incubator (37°C), Ice Bath (1°C), and Boiling Water (100°C)

• Dependent Variable( the variable that is observed and responds to the change made to the independent variable) = Amount of glucose produced measured in milligrams per decilitres

• Controlled Variables ( the variables that are kept constant) = Amount of Sucrose solution in each test tube ( 3 mL), Type of sucrose/sugar, amount of yeast in un-controlled test tubes (0.5g), type of yeast, and amount of time the test tubes are left in different temperature conditions (15 minutes)

Control Set Up• We set up a control group by simply not

adding any yeast to four of the test tubes. • We put one of these controlled test tubes in

each of the 4 different temperature conditions.

• We put one in room temperature, one in the incubator, one in the ice bath and one in the boiling water bath.

Room Temperature Incubator

Ice Bath Boiling Water

ResultsTest Tube Glucose

Formation @ Room Temp. (20°C)

Glucose Formation in Incubator (37°C)

Glucose Formation in Ice Bathe (-1°C)

Glucose Formation in Boiling Water (100°C)

#1 150mg/dL 250mg/dL 800mg/dL 1200mg/dL

#2 100mg/dL 300mg/dL 850mg/dL 1000mg/dL

#3 200mg/dL 350mg/dL 900mg/dL 1250mg/dL

Control negative negative negative negative

Glucose Formation in mg/dL at each Temperature Condition

Room Temp. Incubator Ice Bath Boiling Water0

200

400

600

800

1000

1200

1400

Test tube # 1Test Tube #2Test Tube #3Control

Overall Outcome• Our lab experiment outcome was fairly inaccurate• Our results were supposed to favour the tests in the incubator

however; they actually favoured the boiling water. • These results are incorrect because yeast; like enzymes is sensitive to

temperature. The boiling water should have killed the yeast and denatured the sucrase enzymes; therefore there should have been very little if any glucose formation.

• The Ice bath also should have slowed down the enzyme’s activity and not of produced as much glucose as it did.

• The incubator is the most accurate representation of the temperature in the human body (37°C) therefore; the sucrase in the yeast should have produced more glucose in that test but for some reason that we can’t understand it did not.

Improvements• More replications• Leave the test tubes for longer then 15 minutes• Test for glucose immediately after the time is up

instead of waiting around trying to find enough glucose test strips

• Do experiment outside class time so that other students don’t keep opening the incubator and interrupting the experiment

The End!Hope you Have a

Very Merry Christmas and a

Happy New Year

Christmas CarolSucrase The Digestive Enzyme (to the tune of Rudolf the Red-Nosed Reindeer)

Sucrase, the digestive enzymehas a very active site.

And if you find its substrate, you would even say it fits (like a puzzle)

All of the other enzymes

used to bind and make new thingsthey never let poor Sucrasejoin in any enzyme games

Then one chemical reactionSucrose came to say:

"Sucrase with your active site,” won't you bind with me tonight?"

Then all the enzymes joined inAs glucose and fructose were formed

Sucrase the digestive enzyme you'll produce monosaccharide’s