9/27/10

Yunsu Y.

Enzyme Lab

Today the whole class time was devoted to the Enzyme Lab.

1. Catalase:

• An enzyme thats speeds up the reaction which breaks down hydrogen peroxide (H2O2) into two harmless substances: water (H2o) and oxygen (O2).
• This ties into the Enzyme Lab that we did today because if the bubbles were seen as a reaction in the test tubes, then the catalase was in action and broke up the hydrogen peroxide into water and oxygen.

2. Control Group:

• Test tube filled with catalse to 1cm and 4cm of hydrogen peroxide.
• This is the control group because the rest of the experiments are based off of this result.

* Purpose:The catalase is present to break down the hydrogen peroxide, but when substituted with a different substrate then will the same reaction occur? This was the focus of the lab.

3. Temperature

• We all know that when something is colder in temperature then the slower chemical reactions are. The warmer the temperature the chemical reaction speeds up.
• On the other hand, for enzymes the temperature has to be optimal for it to work properly. If the temperature is too hot then the heat will cause the enzyme to uncomfortable and even to denature. This goes the same when the temperature is too cold for the enzyme.
• By testing the tubes in the refrigerator, incubator, and in the boiling water, we could look at the results to see at what temperature the enzymes find optimal. (At which temperature the catalase works the best, breaking down the hydrogen peroxide.)

4. pH Level

• We used 3 different liquids with 3 different pH levels. One with HCl solution pH3-acidic, distilled water pH7-neutral, and NaOH pH11-base.
• The optimum pH level for catalase is 7, which is neutral, in this case the distilled water. Similar to the temperature, if the pH level is too acidic or too much of a base then the enzyme will denature causing it to be unable to breakdown the hydrogen peroxide=no bubbles.

Homework:

-Finish Enzyme Lab (questions)

-Mini Assignment due TOMORROW! (pg. 3 Tanning Beds and Skin Cancer)

Next Scribe: Sonali P.