1 Pre – AP 10/11 Warm – UP Notes Enzymes and Bioenergetics (CH 2 section 4) HW: Print Enzyme Lab (posted today) Study for Quiz FRIDAY. Check your assignment for PSAT

2 Warm - UP What are enzymes and what do they do?

3 Enzymes

4 What Are Enzymes? Proteins ( Most enzymes are Proteins (tertiary and quaternary structures) Catalyst Act as Catalyst to accelerates a reaction Not permanently Not permanently changed in the process

5 Enzymes catalyze Are specific for what they will catalyze Reusable Are Reusable ase End in –ase-Sucrase-Lactase-Maltase

6 How do enzymes Work? weakening bonds owers Enzymes work by weakening bonds which lowers activation energy

7 Enzymes Free Energy Progress of the reaction Reactants Products Free energy of activation Without Enzyme With Enzyme

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10 Enzyme-Substrate Complex substance enzyme substrate The substance (reactant) an enzyme acts on is the substrate Enzyme Substrate Joins

11 Active Site restricted region enzyme bindssubstrate A restricted region of an enzyme molecule which binds to the substrate. Enzyme Substrate Active Site

12 Induced Fit shape A change in the shape of an enzyme’s active site Induced Induced by the substrate Different from lock and key analogy

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14 Factors Affecting Enzyme Activity Temperature pH Cofactors & Coenzymes Inhibitors

15 Temperature & pH Most enzymes like near neutral pH (6 to 8) ionic salts Denatured (unfolded) by ionic salts High temperatures denature (Most like normal Body temperatures High temperatures are the most dangerous reactions & denature enzymes (Most like normal Body temperatures)

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17 Cofactors and Coenzymes Cofactors: Inorganic substances (zinc, iron) Cofactors: Inorganic substances (zinc, iron) and Coenzymes: vitamins enzymatic activity Coenzymes: vitamins (organic) are sometimes need for proper enzymatic activity. Example: Example: Iron hemoglobin oxygen Iron must be present in the quaternary structure of hemoglobin in order for it to pick up oxygen.

18 Two examples of Enzyme Inhibitors a. Competitive inhibitors: resembleenzyme’s normal substrate competeactive site a. Competitive inhibitors: are chemicals that resemble an enzyme’s normal substrate and compete with it for the active site. Enzyme Competitive inhibitor Substrate

19 Inhibitors b.Noncompetitive inhibitors: do not enter the active sitebind to another part enzymeenzymechange its shapealters the active site Inhibitors that do not enter the active site, but bind to another part of the enzyme causing the enzyme to change its shape, which in turn alters the active site. Enzyme active site altered Noncompetitive Inhibitor Substrate

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21 BIOENERGETIC S

22 What is Bioenergetics? energyliving systems organisms The study of energy in living systems (environments) and the organisms (plants and animals) that utilize them

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24 Energy Required by all organisms May be Kinetic or Potential energy

25 Kinetic Energy Energy of Motion Heat and light energy are examples

26 Kinetic Energy

27 Potential Energy Energy of position Energy of position Includes energy stored in chemical bonds; chemical gradients Includes energy stored in chemical bonds; chemical gradients

28 Two Types of Energy Reactions

29 Endergonic Reactions Chemical reaction energy Chemical reaction that requires a net input of energy. (energy absorbing) Photosynthesis Photosynthesis 6CO 2 +6H 2 O  C 6 H 12 O 6 + 6O 2 SUN photons Light Energy (glucose)

30 Exergonic Reactions Chemical reactions releases energy (energy releasing) Chemical reactions that releases energy (energy releasing) Cellular Respiration C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O+ ATP (glucose)Energy

31 Metabolic Reactions of Cells

32 What is Metabolism? sum total chemical activities cells The sum total of the chemical activities of all cells.

33 Two Types of Metabolism Anabolic Pathways Anabolic Pathways Catabolic Pathways Catabolic Pathways

34 Anabolic Pathway Metabolic reactions, consume energy(endergonic), build Metabolic reactions, which consume energy (endergonic), to build complicated molecules from simpler compounds. Photosynthesis Photosynthesis 6CO 2 + 6H 2 O  C 6 H 12 O 6 + 6O 2 SUN lightenergy (glucose)

35 Catabolic Pathway Metabolic reactions release energy (exergonic)breaking down Metabolic reactions which release energy (exergonic) by breaking down complex molecules in simpler compounds Cellular Respiration Cellular Respiration C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + ATP (glucose) energy

36 Cellular Energy - ATP

37 ATP Components: Components: 1. adenine: nitrogenous base 2. ribose: five carbon sugar 3.phosphate group: chain of 3 ribose adenine PPP phosphate group

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39 Adenosine Triphosphate Three phosphate groups-(two with high energy bonds Three phosphate groups-(two with high energy bonds Last phosphate group (PO 4 ) contains the MOST energy Last phosphate group (PO 4 ) contains the MOST energy

40 Breaking the Bonds of ATP phosphorylation Process is called phosphorylation Occurs continually in cells ATP-ase last PO 4 bond Enzyme ATP-ase can weaken & break last PO 4 bond releasing energy & free PO 4

41 How does ATP work ? enzymes energy-rich glucose Organisms use enzymes to break down energy-rich glucose to release its potential energy adenosine triphosphate(ATP) This energy is trapped and stored in the form of adenosine triphosphate(ATP)

42 How Much ATP Do Cells Use? each cell 10,000,000 molecules of ATP per second It is estimated that each cell will generate and consume approximately 10,000,000 molecules of ATP per second

43 Coupled Reaction - ATP exergonic hydrolysis ATP endergonic dehydration process transferring phosphate group The exergonic hydrolysis of ATP is coupled with the endergonic dehydration process by transferring a phosphate group to another molecule. H2OH2OH2OH2O H2OH2OH2OH2O

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45 Hydrolysis of ATP ATP + H 2 O  ADP + P (exergonic) Hydrolysis (add water) PPP Adenosine triphosphate (ATP) PP P + Adenosine diphosphate (ADP)

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47 Hyrolysis is Exergonic Energy Used by Cells

48 Dehydration of ATP ADP + P  ATP + H 2 O (endergonic ADP + P  ATP + H 2 O (endergonic ) PPP Adenosine triphosphate (ATP) PP P + Adenosine diphosphate (ADP) Dehydration (Remove H 2 O

49 Dehydration is Endergonic Energy is restored in Chemical Bonds

50 Review

51 How many high energy phosphate bonds does ATP have?

52 Which is true of photosyntheis? Anabolic or Catabolic ExergonicOrEndergonic

53 The breakdown of ATP is due to: DehydrationorHydrolysis H 2 O addedorH 2 O removed

54 Which Reactions are often Coupled in Organisms Hydrolysis or Dehydration Anabolism or Catabolism EndergonicorExergonic BOTH BOTH BOTH