1.Draw a graph that shows the relative changes in your mood during the course of a school day.

Include: An hour scale of one day; Title your graph.

2. Describe your graph in words.

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Dependent variable: The one of which values change according to the experimental conditions. Goes on the Y. (Here – your mood)

Independent variable: The one that I manipulated by the person running the experiment. Goes on the X.(here and often – Time that passed)

Variables of an experiment:

Draw the graph.

Next to each of the arrows draw a protein (like a ‘toober’), either in its native, working state, or in its open non-working state.

Temperature (oC)E

nzy

me

acti

vity

A

B

C

Draw the following two graphs.

pH1471

En

zym

e ac

tivi

ty

Temperature (oC)E

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acti

vity

JA liver enzyme called CATALASE speeds up the following reaction:

H2O2 O2 (gas)+ H2O(Hydrogen peroxide)

1. What are the substrate(s) and product(s) of the reaction? What should be the source of the enzyme?

2. Which substance can indicate that the reaction took place?

Demonstration: How to observe catalase activity – The disc floating test.

Your task TODAY:

Try out the catalase reactionTHINK:

-How will you show that the enzyme is necessary?

-How will you show that the substrate is necessary?

Today you will observe the activity of liver catalase.1. Describe the procedure of

measuring the enzyme activity using the paper-disc test.

2. How would you show that both enzyme and substrate are necessary for the reaction?

Catalase Animation

Catalase Animation

Group challenge no. 1:1. Try out the paper disc test for

liver catalase.

2. How will you prove that both enzyme and substrate are necessary for the reaction?

3. Record your experience so far in each of your notebooks.

1. Student 1 added the liver-disc, added peroxide, heated the test-tube. The disc floated quickly. What can be concluded?

2. After trying several conditions for catalase, student 2 tried a paper disc without liver extract, added H2O2, the disc floated. What happened?

Group - Experimental Planning1. Write and draw your plan.2. Follow the checklist

directions.3. Show your teacher before you

start.

(Write title)“Effect of temperature and pH on catalase activity”

Back to planning:•List the 7 test tubes that you need.•For each test tube, describe what you will do IN DETAIL:

- materials, order, amount, temp.•Look up the rubric – see that all requirements are met!•Show teacher•If OK’ed – do it!

Reflect on the Enzyme Lab:1. How did you feel when you

were given less directions on how to do the experiment?

2. How do the effects of temperature and pH on the enzyme show the Lock & Key principle? Explain.

Lab Summary:Write your plan according to the grading check list.•If you did the experiment – write as if you will improve it.

+ Include your results!Next to your predictions!

•If you did not – write as if you will do it, based on others’ experience.

Lab Report:

PART TWO: Planning

PART THREE: Describe Results

PART FOUR: Conclude, regarding background

PART ONE: Background- Importance, Reaction

Group challenge no. 2:Plan an experiment that will test

the effect of temperature and pH on liver catalase activity.

A. How will you manipulate pH and temperature?

- Plan materials/equipment- Plan order of operationsB. How will you keep all other

conditions as constants?

1. Student 1 added the liver-disc, added peroxide, heated the test-tube. The disc floated quickly. What can be concluded?

2. Student 2 added the liver-disc, then added acid. The disc did not float. What can be concluded?

Lab: Groups that completed the pre-lab questions and can explain their procedures, may begin. Finish lab early – may complete group report IN CLASS.

1) List three facts that you learned so far about enzymes.

2) Write one question you have about enzymes (for understanding / curiosity)

Notes

Principles of Enzymes

1. Enzymes are recycled.2. Enzymes catalyze (speed up)

reactions but do not change the type of their products.

3. An Enzyme’s shape must fit its substrate, and only the right substrate!

4. Enzymes reduce the activation energy of the reaction.

The lock and Key model

Draw the following chart:

Enzyme Substrate Product

Saliva Amylase

Starch Glucose

Papain (protease)

Catalase

How enzymes form - animation

Graphing Activity: Group

Draw the graphs in your notebook. Copy the graphs onto a poster paper.

More on the poster: -Draw the enzyme’s shape at different temperatures and pH.

-Show substrate and product.-Give your poster a smashy title!

catalyst

enzymes

substrate

product

Chemical reaction

Active site

Activation energy

Lock&Key Model

Tube 1 Tube 2 Tube 3 Tube 4Water - Water -

- Starch - Starch

- - Saliva Saliva

Period 1

Period 5

1. Describe the results in the two class periods.

2. Why were the results in period 5 different than in period 2?

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Tube 1 Tube 2 Tube 3 Tube 4Water - Water -

- Starch - Starch

- - Saliva Saliva

Tube 1 Tube 2 Tube 3 Tube 4Water - Water -

- Starch - Starch

- - Saliva Saliva

Period 3

Period 5

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Using Gelatin and pineapple to demonstrate enzyme activity.

* Gelatin: A protein from animal connective tissues. Usually prepared from cows or pigs.* It is recommended not to use pineapple or papaya in the mix.Why? * Pineapple, papaya contain enzymes that break down proteins to…

Pineapple and Jell-O:

Reaction:

Identify: enzyme, substrate, products