Chemistry of Organisms 9 - BIOLOGY JUNCTION

Catalase Bi Sample Lab 2

Enzyme Rate of Reaction for Catalase

Introduction:
Life would not be possible without chemical reactions. Chemical reactions are responsible for speeding up the process. A chemical reaction is the process of breaking chemical bonds, forming new bonds or both. The four things that can speed up a chemical reaction is heat, increasing the concentration of reactants, decreasing the concentration of products, and enzymes. Enzyme is a catalase, most the time a protein. Enzymes can control the rate of a reaction, and they also lower activation energy. Enzymes are important in regulating chemical pathways, synthesizing materials needed by cells, releasing energy, and transferring information. Enzymes are involved in digestion, respiration, vision, movement, and thought. There are several things that can affect the function of enzymes like temperature, the pH, and the amount of reactant or product. Simple cells may have as many as 2000 different enzymes, each one catalyzing a different reaction. In this particular lab, your hands act as the enzyme “Catalase”. This enzyme, which is found in your cells, splits hydrogen peroxide, a byproduct made by your cells during cellular respiration, into water and oxygen.

Hypothesis:
If time is increased, then more hydrogen peroxide molecules will be split into water and oxygen

Materials:
The materials used in this lab were pencils, scissors, envelope, 100 paper hydrogen peroxide molecules, and a watch with a second hand so that a person would be able to keep time for the person tearing the strips.

Methods:
Take a paper template and cut out 100 hydrogen peroxide molecules. Place the cut out pieces into an envelope. Then have a person act as a catalase and take one piece of the paper molecules out of the envelope at a time and rip it in two and place the pieces back into the envelope. Have a person hold the envelope person, while another student keeps track of the “tearing” time intervals (10, 20, 30 ,60, and 60 seconds). Count how many molecules are ripped at the end of each time interval and record this number in your data table. When all time intervals and counts are completed, use the formula below to figure the reaction rate for catalase. Record this rate in your data table.
M2 – M1 = reaction rate
T2 – T1

Results:

Time in seconds	Ripped Hydrogen Peroxide Molecules	Rate of reaction
0-10	3	.3
10-30	10	.35
30-60	24	.47
60-120	63	.65
120-180	124	1.02

1. What is an enzyme? What are its functions in living things?
Enzymes are proteins in living systems. Enzymes can control the rate of a reaction, and they lower activation energy.

2. Name several things things that can affect the function of an enzyme?
Temperature, the amount of reactant or product and the pH.

3. Write the chemical equation for the breakdown of hydrogen peroxide by the enzyme catalase.
hydrogen peroxide + catalase yields water + oxygen

4. An enzyme’s efficiency increases with greater substrate concentration, but only up to a point. Why?
all of the active sites of the enzymes become filled with hydrogen peroxide molecules

5. If you were allowed to continue this lab and rip hydrogen peroxide molecules for 240 and 300 seconds. What would happen to the rate of reaction and why would this happen?
It would increase.

6. What can you say about the length of time and the rate of the reaction?
The less time, the more the reaction rate is lowered, and the more time, the more the reaction rate is higher.

7. What would happen to the rate of reaction if you remove the water and oxygen molecules as soon as they are produced?
It would be faster.

Error Analysis:
All pieces must be returned to the envelope each time interval to correctly simulate what occurs within a cell.

Discussion and Conclusion:
As the time intervals increased, the reaction rate of catalase increased also. In a living cell, more hydrogen peroxide would be broken down by catalase over a longer period of time.

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Bioenergetics Powerpoint Worksheet

Bioenergetics
ppt Questions

Energy

1. What is bioenergetics?

2. All organisms require ____________ to perform their functions.

3. Name the 2 main kinds of energy.

4. What is kinetic energy?

5. Give 2 examples of kinetic energy.

6. What is potential energy?

7. Potential energy is stored in ____________ __________.

Two Types of Energy Reactions

8. What is an endergonic reaction?

9. Give an example of an endergonic reaction.

10. What serves as the energy for photosynthesis?

11. During photosynthesis, the light energy is stored in the chemical bonds of what sugar?

12. What are the two raw materials (reactants) for photosynthesis?

13. What is an exergonic reaction?

14. Give an example of an exergonic reaction.

15. Where does the energy for cellular respiration come from?

16. Energy released during cellular respiration that can be used by cells is called _________.

Metabolic Reactions of Cells

17. Define metabolism of cells.

18. From what compound do animals get their energy (ATP) to do cellular work?

19. Name the 2 types of metabolism.

20. Explain anabolic pathways and give an example.

21. Explain catabolic pathways and give an example.

22. The energy that drives catabolic pathways in organisms comes from breaking _____________ ___________ and producing the energy molecule ___________.

Cellular Energy – ATP

23. Name the 3 components that make up ATP.

24. How many phosphate groups are in ATP?

25. The last two phosphate groups on ATP are bonded with ___________ ___________ bonds.

26. Which phosphate bond contains the MOST energy?

27. Give the formula for a phosphate group.

28. Name the process that breaks the bonds of ATP to release energy.

29. How often does phosphorylation occur in cells?

30. What enzyme weakens the last phosphate bond so it can be broken?

31. Organisms use ___________ to break down energy-rich __________ to release the potential energy stored in its bonds.

32. Energy released from the chemical bonds of glucose are trapped & stored in ________ until a cell needs energy.

33. What does ATP stand for?

34. How much ATP do cells use?

35. What coupled reactions make ATP and then release its energy.

36. Is hydrolysis exergonic or endergonic?

37. Is energy stored or released during hydrolysis?

38. Is dehydration exergonic or endergonic?

39. Is energy stored or released in dehydration?

40. When ATP is broken down to release energy, what two things form?

41. During hydrolysis of ATP, a molecule of ___________ is added to split the ________ phosphate bond.

42. What happens to the energy released from the hydrolysis of ATP?

43. During dehydration of ATP, a molecule of ___________ is removed to join a free phosphate and __________ making more ATP again.

44. Where is the energy stored in the dehydration process to form ATP?

Review

45. How many high-energy phosphate bonds does ATP have?

46. Is photosynthesis anabolic or catabolic?

47. Is photosynthesis exergonic or endergonic?

48. The breakdown of ATP is due to hydrolysis or dehydration?

49. Water is added or removed in the breakdown of ATP?

50. Which of the following are coupled reactions in organisms:

a. hydrolysis – dehydration?

b. Anabolism – Catabolism?

c. Endergonic – Exergonic?

AP Lecture Guide 02 & 03 – Chemical Context of Life & Water

AP Biology: CHAPTERS 2 & 3

CHEMICAL CONTEXT OF LIFE & WATER

1. What are the most common elements in the human?

__________________________________________________________________________

2. Helium has an atomic number of 2 and atomic mass of 4. Explain.

__________________________________________________________________________

3. Define isotope and give some examples.

__________________________________________________________________________

4. How are isotopes used in biology?

__________________________________________________________________________

5. What happens when electrons change levels?

__________________________________________________________________________

6. What is the significance of valence numbers?

__________________________________________________________________________

7. Why do atoms form covalent vs. ionic bonds?

__________________________________________________________________________

8. How do non-polar covalent bonds differ from polar covalent bonds?

__________________________________________________________________________

9. What is a hydrogen bond? How does it form and how is it different from a covalent bond?

__________________________________________________________________________

10. Sketch a few molecules of water, indicate their polarity, and where H bonds form.

11. Why is H bonding so important to water’s properties?

__________________________________________________________________________

12. List the “special” properties of water and give an example of why the property may be

important to living things.

a. ________________________________________________________________________

__________________________________________________________________________

b. ________________________________________________________________________

__________________________________________________________________________

c. ________________________________________________________________________

__________________________________________________________________________

d. ________________________________________________________________________

__________________________________________________________________________

Amino Acids

Listed below are the common names and structural formulas of the twenty amino acids found in proteins. They are arranged alphabetically.

alanine

arginine

asparagine

aspartic acid

cysteine

glutamic acid

glutamine

glycine

histidine

isoleucine

leucine

lysine

methionine

phenylalanine

proline

serine

threonine

tryptophan

tyrosine

valine

Amylase on Starch Lab

Enzyme Amylase Action on Starch

INTRODUCTION:

In this experiment you will observe the action of the enzyme amylase on starch. Amylase changes starch into a simpler form: the sugar maltose, which is soluble in water. Amylase is present in our saliva, and begins to act on the starch in our food while still in the mouth.
Exposure to heat or extreme pH (acid or base) will denature proteins. Enzymes, including amylase, are proteins. If denatured, an enzyme can no longer act as a catalyst for the reaction.
Benedict’s solution is a test reagent that reacts positively with simple reducing sugars like maltose, but will not react with starch. A positive test is observed as the formation of a brownish-red cuprous oxide precipitate. A weaker positive test will be yellow to orange.

MATERIALS:

Cornstarch
Distilled water
Saliva
Vinegar
Benedict’s qualitative solution
3 graduated cylinders (10mL)
250-ml beaker
Stirring rod
3 test tubes (16 x 125mm)
Test tube rack
Wax pencil
Water Bath

PRE-LAB:

Add 1g of cornstarch to a beaker containing 100ml of cold distilled water. While stirring frequently, heat the mixture just until it begins to boil. Allow to cool.

PROCEDURE:

1. Fill the 250-mL beaker about 3/4 full of water and place on the hot plate for a boiling water bath. Keep the water JUST AT BOILING.

2. Mark 3 test tubes A, B and C. “Spit” between 1 and 2 mL of saliva into each test tube.

3. Into tube A, add 2 mL of vinegar. Into tubes B and C, add 2 mL of distilled water. Thump the tubes to mix.

4. Place tube B into the boiling water bath for 5 minutes. After the five minutes, remove from the bath, and place back into the test tube rack.

5. Add 5 mL of the starch solution to each tube and thump to mix. Allow the tubes to sit for 10 minutes, occasionally thumping the tubes to mix.

6. Add 5 mL of Benedict’s solution to each tube and thump to mix. Place the tubes in the hot water bath. The reaction takes several minutes to begin.

OBSERVATIONS:

Tube A: Starch + saliva treated with vinegar (acid)

What does this indicate?__________________________________________________

____________________________________________________________________

Tube B: Starch + saliva and water, treated in a boiling water bath

What does this indicate?__________________________________________________

____________________________________________________________________

Tube C: Starch + saliva

What does this indicate?__________________________________________________

____________________________________________________________________

QUESTIONS:

1. What is the function of an enzyme?

2. Where does a substrate attach to an enzyme?

3. If an enzyme is present in a reaction, less ________________ _________________ will be needed to get the reaction started.

4. What is a common suffix found at the end of most biological enzymes?

5. Most enzymes are macromolecules called ________________.

6. Define denaturation of proteins.

7. Name 3 things that can denature or unfold an enzyme.

8. In this lab, what weak acid denatured the protein?

9. What was the purpose of placing one test tube in a hot water bath?

10. What happens to enzymes in your body whenever you run fever?