Objectives: ◦ Take quiz on energy conversions ◦ Describe how an enzyme works ◦ Complete...
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Objectives: ◦ Take quiz on energy conversions ◦ Describe how an enzyme works ◦ Complete toothpick enzyme lab Review Questions: ◦ 1. What does the Law of Conservation of Energy say? ◦ 2. What type of energy conversion does a solar panel on a house carry out? Other Instructions: Turn in vocab., 11x17 Coloring sheet, and fill-in-the-blank from yesterday
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Transcript of Objectives: ◦ Take quiz on energy conversions ◦ Describe how an enzyme works ◦ Complete...
Objectives:◦ Take quiz on energy conversions◦ Describe how an enzyme works◦ Complete toothpick enzyme lab
Review Questions:◦ 1. What does the Law of Conservation of Energy say?
◦ 2. What type of energy conversion does a solar panel on a house carry out?
Other Instructions: Turn in vocab., 11x17 Coloring sheet, and fill-in-the-blank from
yesterday
What happens to chemical bonds during chemical reactions?
How do energy changes affect whether a chemical reaction will occur?
Why are enzymes important to living things?
Living things are made up of chemical compounds
Everything that happens to an organism is based on chemical reactions
A process that changes or transforms one set of chemicals into another
Elements or compounds that enter into a reaction
Elements or compounds produced by a chemical reaction
In the blood
In the lungs
CO2 + H20 H2CO3 (carbonic acid)
H2CO3 CO2 + H2O
Released as you breathe
Energy-Absorbing Reaction Energy-Releasing Reaction
Products
Products
Activation energy
Activation energy
Reactants
Reactants
The energy that is needed to get a reaction started
Some chemical reactions are too slow or have activation energies that are too high to make them practical for living tissue
These chemical reactions are made possible by catalysts
Substance that speeds up the rate of chemical reactions
Work by lowering a reactions activation energy
Are known as Biological catalysts
Speed up reactions in cellsVery specific name for the reaction is catylzes
Enzyme names always end in -ase
Reaction pathwaywithout enzyme Activation energy
without enzyme
Activationenergywith enzyme
Reaction pathwaywith enzyme
Reactants
Products
The reactants of enzyme catalyzed reactions
The active site of the enzyme and the substrate have complementary shapes
Fit like a lock and key
Enzyme – substrate complex
Glucose
Substrates
ATP
Substratesbind toenzyme
Substratesare convertedinto products
Enzyme-substratecomplex
Enzyme(hexokinase)ADP
Products
Glucose-6-phosphate
Productsare released
Active site
Enzymes are affected by any variable that affects chemical reactions
1. pH2. Temperature3. Concentration
of enzyme
1. What happens to chemical bonds during chemical reactionsBonds are broken in reactants and new bonds are formed in products
2. Describe the role of energy in chemical reactionssome chemical reactions release energy, and other chemical reactions absorb energy. Energy changes determine how easily a chemical reaction will occur
3. What are enzymes, and how are they important to living things?Enzymes are biological catylasts. Cells use enzymes to speed up virtually every important chemical reaction that takes place in cells
4. Describe how enzymes work, including the role of the enzyme substrate complexSubstrates, the reactants of an enzyme-catylzed reaction, attach to the enzyme at an active site and form an enzyme – substrate complex. Once the complex is formed, the enzyme helps convert substrate into product
5. A change in pH can change the protein. How might a change in pH affect the function of an enzyme such as hexokinase (hint: think about the analogy of the lock and key)A change in pH could change the shape of hexokinase. This change would diminish the ability of glucose and ATP to bind to the active site of the enzyme.
1. Temperature (high and low)2. pH (generally low)3. enzyme concentration
Enzyme is denatured, which means that it changes shape such that it can no longer bind to the substrate
More enzyme available (higher enzyme concentration = reaction happens faster) more product made
Low pH tends to break hydrogen bonds, changing the shape of the enzyme (denatured) so that it can no longer bind to the substrate
1. What happens to chemical bonds during chemical reactionsBonds are broken in reactants and new bonds are formed in products
2. Describe the role of energy in chemical reactionssome chemical reactions release energy, and other chemical reactions absorb energy. Energy changes determine how easily a chemical reaction will occur
3. What are enzymes, and how are they important to living things?Enzymes are biological catylasts. Cells use enzymes to speed up virtually every important chemical reaction that takes place in cells
4. Describe how enzymes work, including the role of the enzyme substrate complexSubstrates, the reactants of an enzyme-catylzed reaction, attach to the enzyme at an active site and form an enzyme – substrate complex. Once the complex is formed, the enzyme helps convert substrate into product
5. A change in pH can change the protein. How might a change in pH affect the function of an enzyme such as hexokinase (hint: think about the analogy of the lock and key)A change in pH could change the shape of hexokinase. This change would diminish the ability of glucose and ATP to bind to the active site of the enzyme.
