BIOLOGY 12: C
HAPTER
6 R
EVIEW
W
ORKSHEET
E
NZYMES
P
ART
A: C
HAPTER
R
EVIEW
1. List the 2 cellular organelles that transform one form of energy into another form.
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2. Name the 2 processes that permit a flow of energy from the sun through all living things?
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3. Define energy. Do chemicals, energy, or both cycle through living things?
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4. Define the First Law of Thermodynamics. Can energy be converted from one form to another form?
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5. Why must a cell always take in energy in order to continue living?
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6. What is meant by the Second Law of Thermodynamics? What form of energy is lost to the surroundings?
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7. Name the molecule that is the immediate source of energy in cells. What is it composed of? Where are the high-energy bonds found? _______________________________________________________________________________________________________
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8. Define metabolism. What are the advantages of having metabolic pathways in a cell?
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9. What are enzymes? Why are they important? Are they specific? How are they named?
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10. Why are enzymes absolutely necessary to the continued existence of a cell?
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P
ART
B: O
BJECTIVE
C
HAPTER
T
EST
1.
When cells require energy for synthetic reactions, they “spend” _______________.
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2. In the diagram below, list the two cellular processes that allow for energy transformations on lines a and b. One lines c and d, list the organelles responsible for each cellular process. a. _______________________ b. _______________________ carbohydrate + O
2 c. _______________________ d. _______________________
CO
2
+ H
2
O
ATP + heat
3. According to the Second Law of Thermodynamics, one usable form of energy _____________ ( can/cannot ) be completely converted into another usable form.
4. ____________ is the non-usable form of energy that is easily lost to the surroundings.
5. Every ATP molecule is composed of the base (a) _______________, the sugar (b) _____________, and three (c)
____________________ groups. The wavy lines in the formula for ATP indicate (d) _________-___________ phosphate bonds.
6. The equation ADP +
7.
 ATP is energy ____________________ (requiring/releasing)
E1 E2 E3
A  > B  > C  > D
In this metabolic pathway, the letter B stands for the (a) _______________ as the result of the action of Enzyme 1.
However, as a result of the action of Enzyme 2, B represents a (b) _____________. Each and every reaction in a cell requires a specific (c) ______________.
8. The generalized equation for enzymatic action is _____________________________.
This equation shows that the enzyme and the substrate form a temporary __________________ complex.
9. __________________ is an enzyme that removes hydrogen atoms from a substrate.
Enzyme Substrate a. Lipid a. b. Urea b. c. Starch c. d. Ribonucleic acid d.
10. Less heat is needed to bring about a chemical reaction within a cell because enzymes will _______________
(increase/decrease) the energy of activation of a reaction.
11. The ____________ site is the place where the substrate fits onto the enzyme for orientation so that the reaction takes place.
12. Use the following terms to label this diagram: substrate, enzyme, active site, product, enzyme–substrate complex.
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13. When the substrate binds to the enzyme, the enzyme undergoes a slight change in shape to achieve maximum fit. This concept is termed the ______________ model.
14. Suppose two amino acids join together to form a dipeptide. This type of reaction is considered a ______________
(synthetic / degradation) reaction.
15. Catalase is an enzyme that breaks down hydrogen peroxide into water and oxygen. Plot the results of the data below in the accompanying graph.
Millilitres of Oxygen Temperature
Formed per Minute (  C)
 
100 10
200 20
300 30
600
300
100
40
50
60
16. On the basis of the above graph, at which temperature did the catalase exhibit the greatest activity? __________
17. Why did the activity of catalase decrease as the temperature continued to increase above 40  C?
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18. Explain why hydrogen peroxide can be broken down by the enzyme catalase but another substrate, such as maltose, cannot be broken down by catalase. _________________________________________________________________________________.
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Substrate Concentration
(Milligrams/millilitre)
0
10
20
30
Amount of Product Formed
(Milligrams/millilitre)
40
50
19. Study the table given above.
Which substrate concentration will initially yield the maximum amount of product formed?
0
100
200
400
400
400
(a) ______________________
Explain why the amount of product formed does not increase as the substrate concentration goes beyond 30 milligrams/ml.
(b) _____________________________________________________________________________________________________________________
20. Based on the 2 tables presented below, which shows irreversible inhibition ? ________________________
Substrate Concentration
(milligrams/millilitre)
Table A
Inhibitor Concentration
(milligrams/millilitre)
Amount of Product Formed
(milligrams/millilitre)
20
20
20
20
100
Substrate Concentration
(milligrams/millilitre)
20
20
20
0
10
20
40
40
Table B
Inhibitor Concentration
(milligrams/millilitre)
0
10
20
200
100
50
0
400
Amount of Product Formed
(milligrams/millilitre)
200
0
0
20
100
40
40
0
0
21. In ________________ inhibition, an inhibitor binds to an enzyme at a site other than the active site.
22. Two environmental factors that can change the shape of an enzyme are (a) ____________ and (b) ________.
23. Enzymes may have a non-protein helper called a(n) (a) _____________ or an organic molecules called a(n) (b)
____________________.
24. _____________________ is the loss of electrons or the removal of hydrogen atoms.
For questions 27-31, use the following answers to match with the words below. a. inhibitor b. ATP c. enzyme d. extreme temperature
25. denatured
26. substance that can compete with a substrate
27. energy currency of the cell
28. substance that can speed up one particular reaction
___________
___________
___________
___________
True (T) or False (F) If the statement to be false, rewrite the statement as a true one.
29. Enzymes, being molecules that speed up chemical reactions, are required in photosynthesis and cellular metabolism.
Answer: _______ Restatement:
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30. The shape of an inhibitor molecule is very similar to the shape of the enzyme’s substrate.
Answer: _______ Restatement:
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31. High temperatures and extreme pH can cause an enzyme to denature.
Answer: _______ Restatement:
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32. All enzymes function at the same pH.
Answer: _______ Restatement:
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33. The First Law of Thermodynamics states that one usable form of energy cannot be completely converted into another usable form.
Answer: _______ Restatement:
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34. What are T3 and T4? Where are they secreted from? What are their effects on the body?
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35. What is calcitonin? Under what conditions is it secreted?
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