1. Chemical Reactions And Enzymes
Biology
Mr. Velekei

2. Vocabulary Activation Energy Catalyst Coenzyme Enzyme
Inhibitor Molecule
Product
Reactant
Substrate

3. Chemical Reactions and Enzymes

4. Chemical Reactions and Enzymes
chemical reaction: process that changes one set of compounds (reactants) into another set of compounds (products)

5. Chemical Reactions and Enzymes
chemical reaction: process that changes one set of compounds (reactants) into another set of compounds (products)
A. example:
wood + oxygen  carbon dioxide + water + energy

6. Chemical Reactions and Enzymes
chemical reaction: process that changes one set of compounds (reactants) into another set of compounds (products)
A. example:
wood + oxygen  carbon dioxide + water + energy
Reactants

7. Chemical Reactions and Enzymes
chemical reaction: process that changes one set of compounds (reactants) into another set of compounds (products)
A. example:
wood + oxygen  carbon dioxide + water + energy
Reactants Products

8. The elements or compounds produced at the end of a chemical reaction
Reactants:
The elements or compounds present at the beginning of a chemical reaction
Products:
The elements or compounds produced at the end of a chemical reaction

9. Chemical Reactions and Enzymes
B. example:
carbon dioxide + water  glucose + oxygen

10. Chemical reactions:
Always involve changes in the chemical bonds that joins atoms in compounds.

11. Chemical Reactions and Enzymes
B. example:
carbon dioxide + water  glucose + oxygen
Reactants

12. Chemical Reactions and Enzymes
B. example:
carbon dioxide + water  glucose + oxygen
Reactants Products

13. Chemical Reactions and Enzymes
B. example:
carbon dioxide + water  glucose + oxygen
Reactants Products
chemical equation:
CO H2O  C6H12O6 + O2

14. Chemical Reactions and Enzymes
B. example:
carbon dioxide + water  glucose + oxygen
Reactants Products
chemical equation:
CO H2O  C6H12O6 + O2
Reactants

15. Chemical Reactions and Enzymes
B. example:
carbon dioxide + water  glucose + oxygen
Reactants Products
chemical equation:
CO H2O  C6H12O6 + O2
Reactants Products

16. carbon dioxide + water  glucose + oxygen Reactants Products
How many molecules are in a chemical formula/equation? Photosynthesis:
carbon dioxide + water  glucose + oxygen
Reactants Products
chemical equation:
CO H2O  C6H12O6 + O2
Reactants Products

17. 6CO2 This Molecule is called…. Number of molecules….
Carbon Dioxide
Number of molecules…. 6
Number of Carbon atoms….
Number of Oxygen atoms… 12

18. 6H2O a) This Molecule is called…. Number of molecules….
Water
Number of molecules…. 6
Number of Hydrogen atoms…. 12
Number of Oxygen atoms…

19. Glucose: C6H12O6 b) Glucose or Sugar: Number of molecules….
Number of Carbon Atoms… 6
Number of Hydrogen atoms…. 12
Number of Oxygen atoms…

20. 6O2
c) Oxygen….
Number of molecules…. 6
Number of Oxygen atoms… 12

21. 6CO H2O  C6H12O6 + O2
How many TOTAL ATOMS of each element are present on the REACTANTS side of the reaction:
Carbon: ___________
Oxygen: _____________
Hydrogen: ____________ 6 18 12

22. 6CO H2O  C6H12O6 + O2
How many TOTAL ATOMS of each element are present on the PRODUCTS side of the reaction:
Carbon: ___________
Oxygen: _____________
Hydrogen: ____________ 6 18 12

23. CO2 + H2O  C6H12O6 + O2 6CO2 + 6H2O  C6H12O6 + 6O2
C. Conservation of matter: During a chemical reaction, atoms are not created or destroyed – just rearranged. Therefore, chemical equations must be balanced so there is the same number of atoms on both sides of the equation.
chemical equation:
CO2 + H2O  C6H12O6 + O2
balanced chemical equation
6CO2 + 6H2O  C6H12O6 + 6O2

24. Apply what you’ve LEARNED
a.) 2 H2O2  2H2O O2
# of reactant molecules: 2
# of product molecules: 3
What are the molecules:
Hydrogen Peroxide
Water
Oxygen

25. Apply what you’ve LEARNED
b.) 2 H2O2  2H2O O2
# of reactant atoms: 8
(4 H and 4 O)
# of product atoms: 8
(4H, 2O, 2O)

26. II. Energy in Reactions:
Energy is absorbed or released whenever chemical bonds form or are broken.

27. Chemical reactions that Release energy….
Often Occur Spontaneously (without warning)
Example: Explosion gun powder or fireworks
EXOTHERMIC

28. Chemical reactions that Absorb energy….
Will not occur without a source of energy.
Example: Instant Ice Packs or Photosynthesis.
ENDOTHERMIC

29. The speed of a reaction depends on whether is absorbs or releases energy.

30. Chemical Reactions and Enzymes
II. The speed of a reaction depends on whether it releases or absorbs energy.
Activation
energy
Products
Activation
energy
Reactants
Products
Reactants
Energy Absorbing
Endothermic
Energy Releasing
Exothermic

31. Chemical Reactions and Enzymes
All reactions require some energy to start: activation energy.

32. Chemical Reactions and Enzymes
All reactions require some energy to start: activation energy.
catalyst: substance that speeds up a chemical reaction by lowering the activation energy

33. Chemical Reactions and Enzymes
All reactions require some energy to start: activation energy.
catalyst: substance that speeds up a chemical reaction by lowering the activation energy
Catalysts found in living things are called enzymes
Enzymes are made of Proteins

34. Chemical Reactions and Enzymes
C. Enzymes
provide a site where the reactants of a chemical reaction can be brought together

35. Chemical Reactions and Enzymes
C. Enzymes
provide a site where the reactants of a chemical reaction can be brought together
are not used up or changed during the chemical reaction

36. Chemical Reactions and Enzymes
active site: part of the enzyme where the reactants bind (stick)

37. Chemical Reactions and Enzymes
active site: part of the enzyme where the reactants bind (stick)
reactants: called substrate when they stick to the enzyme

38. Chemical Reactions and Enzymes
active site: part of the enzyme where the reactants bind (stick)
reactants: called substrate when they are in a reaction with an enzyme
substrate only fits into the active site of the correct enzyme (like a key and lock)

39. Labeled diagram:
Enzyme
Active Site
Reactants

40. III. How does an enzyme work? A. reactant binds to the enzyme
Reactant stuck to Active Site
Active Site
Reactants

41. III. How does an enzyme work? A. Reactant binds to the enzyme
Reactant stuck to Active Site
Active Site

42. III. How does an enzyme work? B. reactants converted to product
Active Site

43. III. How does an enzyme work. C
III. How does an enzyme work? C. products are released – enzyme is free to bind new reactant
Enzyme
Product
Active Site

44. A. temperature: destroys the shape of the enzyme (protein)
IV. Enzymes only work in specific conditions
A. temperature: destroys the shape of the enzyme (protein)
B. pH: changes the shape of the enzyme and its active site

45. Temperature or pH Change:
Enzyme
Product
Active Site
No Product Made

46. IV. Enzymes only work in specific conditions
C. inhibitor molecules: block reactant from entering active site

47. Inhibitor Molecules:
Enzyme
Product
Active Site
No Product Made

48. IV. Enzymes only work in specific conditions
D. coenzymes: make enzymes work better

49. Enzyme: Peroxidase in liver cells Reactants: Hydrogen peroxide
Active Site

50. Enzyme: Peroxidase in liver cells Reactants: Hydrogen peroxide
Active Site

51. Enzyme: Peroxidase in liver cells Products: Water and Oxygen
H2O
Active Site

52. Enzyme: Peroxidase in liver cells Products: Water and Oxygen
More
Hydrogen Peroxide
Active Site O2
H2O
Product

53. Substrate Concentration
The reaction rate increases until the enzymes become saturated with substrate, and a maximum rate is reached