How Enzymes Work

Lesson Plan

State Standards:


Essential Question:

Why do enzymes work?

Lesson Question:

How fast do enzymes work and what factors can effect the rate?


The cells in your body use and breakdown materials to to manufacture compounds and for energy needed for life processes. A waste product of this breakdown is a chemical called hydrogen peroxide. Hydrogen peroxide is a poison and must be converted into non-hamful products by the cells. The cells make an type of protein called an enzyme that converts hydrogen peroxide into water and oxygen.


Students will observe an enzyme chemical reaction, then design and conduct an experiment to measure the "rate of reaction".

Additionally the students will incorporate certain variables to determine if they effect enzyme activity.

Students should view the video, Enzymes, below prior to conducting the experiment:

The video can also be accessed on YouTube here: Enzyme YouTube video.

Students will graph their findings.

Lesson Experiences:

  1. In your group you will have fresh beef liver and hydrogen peroxide. Place a small piece of liver in a test tube, then add 10ml of hydrogen peroxide. Observe the reaction.
  2. Groups will design and conduct an experiment to measure the rate of the reaction. This will be accomplished by reducing amounts of liver or hydrogen peroxide.
  3. Groups will write findings on the whiteboard and a class average will be determined.
  4. Groups will be given a different variable to incorporate into their experimental procedure. ( HCl, NaOH, Ice Bath, Hot water bath)
  5. All students will then graph results.


Through an inquiry based lesson, students will observe and measure enzyme activity. Additionally, students will observe and measure factors that effect enzyme activity such as temperature and pH.


How Enzymes Work Lesson Rubric



  1. LCD projector
  2. fresh beef liver
  3. hydrogen peroxide
  4. HCl
  5. NaOH
  6. water baths
  7. ice
  8. test tubes
  9. graduated cylinder graph paper
  10. pencils