1. Dispatch Give 3 facts about enzymes What does denature mean?
How are we going to denature our enzyme?

2. Announcements Next test Chapters 2-7. POK or chapter notes
Pick up your grade report at lunch TODAY
Meeting today after school so office hours after school tomorrow
To redo Ecology POK, turn in chapter notes

3. Take out prelab

4. Denaturing Enzymes

5. Enzymes are proteins. Proteins are chains of amino acids.

6. Denature=weaken or kill an enzyme by breaking the amino acid bonds.
When an enzyme is denatured, it slowly turns substrate to product or not at all.

7. What can cause an enzyme to denature?
Animation
What can cause an enzyme to denature?

8. Enzyme: Catalase REACTANT H2O2 PRODUCTS O2 H20
What is the equation of this reaction?

12. Denaturing Enzyme
Temperature--Each enzyme has an optimum temperature at which it works best; making the enzyme too hot or too cold will denature it.

14. Denaturing Enzyme
The pH--Each enzyme has an optimal pH that helps maintain its three-dimensional shape; making the enzyme too acidic or basic will denature it.

15. Base
Acid

16. Denaturing Enzyme
The salt concentration--Each enzyme has an optimal salt concentration; making the enzyme too salty will denature it.

17. Your job is to denature an enzyme in the lab and measure its rate of turning a substrate into a product.

18. H202
Catalase
Water
Oxygen Gas

19. Catalase Lab pg 53 Chicken liver has the enzyme catalase.
The substrate is hydrogen peroxide (H2O2).
The products are water (H2O) and oxygen gas (O2).
catalase H2O > 2H2O + O2

20. Materials:
5 test tubes
1 test tube rack
50 ml of catalase
1 ml lemon juice (acid)
1 teaspoon of salt
25 ml of H2O2

21. Control Hot Cold Acid Salt (Temperature) (pH)

22. Procedures pg 53 (cont) Copy and draw each step
1. Label 5 test tubes: Control, Hot, Cold, Acid, Salt
2. Place 10 cm of catalase (enzyme) into each test tube.
3. Make 3 hypothesis, one for temperature, one for pH, and one for salt.
If_____________then
If _____________then
4. Place the test tube labeled temperature in the hot water bath for 3 minutes.
5. Place the test tube labeled cold in the cold water bath for 3 minutes and the test tube labeled room temperature leave in the test tube rack.
6. Add 1ml of lemon juice to the one labeled acid.
7. Add 1 ml of salt to the one labeled salt. Get approval.
8. Add 5ml of H2O2 (substrate) to each of the 5 tubes.
9. Time the reaction with the stop watch and record the height of the bubbles in each tube in cm. Record in Data Table.

23. Laboratory Safety

24. T-1-- Lab Room 7 8 6 2 5 1

25. BEFORE THE LAB

26. Dress properly during a laboratory activity.
Long hair, dangling jewelry, and loose or baggy clothing are a hazard in the laboratory. 
Long hair must be tied back, and dangling jewelry and baggy clothing must be secured.  Shoes must completely cover the foot.  No sandals allowed on lab days.

28. Which shoe is appropriate?

29. Don’t touch, until told
When first entering a science room, do not touch any equipment, chemicals, or other materials in the laboratory area until you are instructed to do so.

30. Where’s the safety equipment?
Know the locations and operating procedures of all safety equipment including: first aid kit(s), and fire extinguisher.  Know where the fire alarm and the exits are located.

31. T-1: Fire Extinguiser is by the door, first aid is by the whiteboard

32. No food
Do not eat food, drink beverages, or chew gum in the laboratory.  Do not use laboratory glassware as containers for food or beverages.

33. Know the directions
Follow ALL written and verbal instructions carefully. If you do not understand a direction or a part of the procedure, ASK YOUR TEACHER BEFORE PROCEEDING WITH THE ACTIVITY!

34. Before the Lab—Answer in complete sentences
1) How do we dress for a lab?
2) What is the rule about food and gum?
3) Can you touch equipment before being told?

35. During the Lab

36. Be responsible
Conduct yourself in a responsible manner at all times in the laboratory.

37. Work together
Never work alone in the laboratory. No student may work in the science classroom without the presence of a teacher.

38. Authorized experiments only!
Perform only those experiments authorized by your teacher. Carefully follow all instructions, both written and oral. Unauthorized experiments are not allowed.

39. Be preapred
Be prepared for your work in the laboratory.  Read all procedures thoroughly before entering the laboratory.  Never fool around in the laboratory.  Horseplay, practical jokes, and pranks are dangerous and prohibited.

40. Keep your area organized
Observe good housekeeping practices.  Work areas should be kept clean and tidy at all times.

41. Don’t wander
Experiments must be personally monitored at all times.  Do not wander around the room, distract other students, startle other students or interfere with the laboratory experiments of others.

42. Goggles on at all times
Any time chemicals, heat, or glassware are used, students will wear safety goggles. NO EXCEPTIONS TO THIS RULE

43. Ask for help
If you do not understand how to use a piece of equipment, ASK THE TEACHER FOR HELP!

44. If there is a problem…

45. YELL FOR HELP
If you or your lab partner is hurt, immediately (and loudly) yell out the teacher's name to get the teacher's attention.  Do not panic.

46. USE the eye wash
If a chemical should splash in your eye(s) or on your skin, immediately flush with running water for at least 20 minutes.  Immediately (and loudly) yell out the teacher's name to get the teacher's attention. 

47. Notify of dangerous hazards
Be alert and proceed with caution at all times in the laboratory.  Notify the teacher immediately of any unsafe conditions you observe

48. Report accidents or injuries
Report any accident (spill, breakage, etc.) or injury (cut, burn, etc.) to the teacher immediately, no matter how trivial it seems.  Do not panic.

49. T-1: Fire Extinguiser is by the door, first aid is by the whiteboard

50. Know what to do in a drill
Know what to do if there is a fire drill during a laboratory period; containers must be closed, and any electrical equipment turned off

51. If there is a problem…
1) What should you do if someone is injured? 2) Where is the first aid located? 3) What do you do if something gets in your eyes?

52. FOR GLASSWARE

53. Use clean, unbroken glassware
Examine glassware before each use.  Never use chipped, cracked, or dirty glassware.

54. Don’t touch broken glass
Never handle broken glass with your bare hands.  Tell the teacher immediately, the teacher will clean it up.

55. Do not immerse hot glassware in cold water. The glassware may shatter.
Nothing hot in the sink
Do not immerse hot glassware in cold water.  The glassware may shatter.

56. Be careful with the hot plate
Do not operate a hot plate by yourself.  Take care that hair, clothing, and hands are a safe distance from the hot plate at all times.  Use of hot plate is only allowed in the presence of the teacher.

57. Use tongs for hot items
Heated glassware remain very hot for a long time.  They should be set aside in a designated place to cool, and picked up with caution.  Use tongs or heat protective gloves if necessary.

58. Don’t watch a boiling test tube
Never look into a container that is being heated.

59. Don’t touch hot plates or test tubes
Do not place hot apparatus directly on the laboratory desk.  Always use an insulated pad.  Allow plenty of time for hot apparatus to cool before touching it.

60. ALWAYS think before you do something!!!!
Always use your brain
ALWAYS think before you do something!!!!

62. For glassware
What things can happen to glassware that you should be aware of?
How should you touch glassware that has been on the hot plate?
Why shouldn’t you look at a boiling test tube?

63. CLEANING UP

64. Wash your hands
Keep hands away from face, eyes, mouth, and body while using chemicals or lab equipment.  Wash your hands with soap and water after performing all experiments.

66. Dispose of chemicals
Dispose of chemicals in waste containers, not down the sink

67. Cleaning
What do you do with the chemicals that you have finished with?
2) What should you do before you leave the lab?

68. Get dressed
Gloves
Aprons