Enzyme - Introductory Biology - Lab Manual, Study notes of Biology

Download Enzyme - Introductory Biology - Lab Manual and more Study notes Biology in PDF only on Docsity! Biochemistry Name: ______________ Enzyme Lab - "Catalysts of Life' Part I. Background Information: Use the Introduction section of your lab to help you answer the questions below. 1. Lots of chemical reactions occur in cells. Give one example of how chemical reactions are used by your cells. __________________________________________________________________________________________ 2. What is an enzyme? __________________________________________ 3. What is a catalyst? _________________________________________________ 4. What would happen to the chemical reactions in your body w/o enzymes? _________________________________ __________________________________________________________________________________________ 5. Is an enzyme itself altered in any way by the chemical reaction that it speeds up? ____________________________ Therefore, can enzymes be re-used? 6. During what process is hydrogen peroxide sometimes produced in cells? _________________________________ 7. What happens in this process? __________________________________________________________________ ________________________________________________________________________________________ 8. What is the chemical formula for hydrogen peroxide? ________________________________________________ 9. What does the enzyme catalase do to hydrogen peroxide? ______________________________________________ 10. Why is catalase necessary in living things? ________________________________________________________ 11. In the space below, write the chemical reaction showing what happens when H2O2 and catalase interact: 12. True or False: Both plants AND animals must break down food molecules to get energy. (circle one) 13. True or False: Both plant cells and animal cells must contain catalase. (circle one) 14. If you add H2O2 to a substance to test for the presence for catalase, what would you expect to observe if the test is positive (catalase present)? _______________________________ negative(catalase not present)? _________________________________ Docsity.com Part II. Making Hypotheses You will be adding H2O2 to 6 different substances. They are: raw hamburger potato tomato water raw liver cooked liver Use the chart below to make hypotheses about which substances you think will contain catalase and which will not and what you would expect to observe (with regard to bubbles) in each case: Hypothesis: Predict what you substance Predict whether substance will observe (bubbles will or will not contain catalase or no bubbles) raw hamburger tomato raw liver potato distilled water cooked liver Part III. Experimental Procedure: You will find at your station the following: cup of water & dropper samples of experimental substances in a Petri dish cup of hydrogen peroxide & dropper forceps 6 labeled test tubes and a rack 1. Be sure to wear goggles!! 2. Obtain 2 ml of distilled water from the cup and place it in the appropriate test tube. NOTE: The top line on the dropper (just before you get to the bulb) is 1 ml. 3. Using forceps, take the sample of each test substance and place it in the appropriate test tube. BE SURE TO RINSE and WIPE OFF the forceps in between touching each of the different substances! Also, do NOT let the substances touch each other! QUESTION: Why should you not allow the substances to touch each other or the same forceps? ___________________________________________________________________________________ 4. Use the dropper in the beaker of H2O2 to place 2ml (2 droppers full) of H2O2 into EVERY test tube in your rack (one at at a time, please) and CAREFULLY OBSERVE EACH REACTION. NOTE the amount of bubbles that form (if any). RECORD your observations in the table on the next page. *CAUTION: Hydrogen peroxide is a strong bleach. Immediately wash with water if any hydrogen peroxide comes in contact with your skin or clothes. Report any spills to your teacher. Docsity.com