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| 8209094191 | Bioenergetics | It is the study of how cells release and store energy in chemical bonds to carry out the necessary life processes. It is the study of how energy from the sun is transformed into energy in living things. | 0 | |
| 8209094192 | Chemical Reaction vs Energy | Every chemical reaction involves a change in energy. Energy is used to create bonds and is released to create bonds. Energy must be first inputed to break chemical bonds to release energy. Enzymes help in this process. | 1 | |
| 8209094193 | Enzymes | They are organic catalysts that speed up the rate of a reaction without changing the reaction itself. They lower the activation energy required and enable the reaction to happen a lot faster. |  | 2 |
| 8209094194 | Exergonic Reactions | They are reactions where the products have less energy than the reactants meaning that energy was lost during the reaction. |  | 3 |
| 8209094195 | Endergonic Reaction | They are reactions where the products have more energy than the reactants meaning that they have gained energy during the reaction. |  | 4 |
| 8209094196 | Activation Energy | It is the energy needed to start a reaction. Even in exergonic reactions where energy is released, there is an activation energy required. |  | 5 |
| 8209094197 | Enzyme Specificity | Each enzyme only catalyzes one reaction. The enzyme would only bind to one molecule or substrate and usually the enzyme is named after it. The enzyme for maltose is called maltase. Usually the name ends with the suffix -ase. | 6 | |
| 8209094198 | Enzyme-Substrate Complex | During a reaction, the enzyme must bring molecules together. It does this at it's active site and when the substrate and enzyme is bound together, it is called an enzyme-substrate complex. After the product is made, the enzyme is free to bind with other substrates. |  | 7 |
| 8209094199 | Functions of Enzymes | They... - increase the rate of reaction by lowering the reactions' activation energy - form temporary enzyme-substrate complexes - remain unaffected by the reaction They don't... - change the reaction - make reactions occur that wouldn't otherwise occur | 8 | |
| 8209094200 | Induced Fit | Sometimes, the substrate doesn't fit perfectly with the enzyme and thus the enzyme must change shape to fit the substrate. | 9 | |
| 8209094201 | Coenzymes | They are there to help the enzyme with catalyzing reactions. Organic coenzymes include vitamins, and they are used to accept electrons and pass them along. NAD+ and NADP+ are examples. Inorganic helpers are called cofactors and they are usually metal ions such as Fe+2. | 10 | |
| 8209094202 | Factors in Reaction Rates | There are 3 factors in the reaction rates: temperature, pH and the concentration of substrate and enzyme. | 11 | |
| 8209094203 | Temperature | The rate of reaction increases with temperature to a point where the enzyme becomes denatured because of heat (usually above 42 C). The increased temperature increases the chance of molecules colliding and thus increases the rate of reaction. Human enzymes usually work best at 37 C | 12 | |
| 8209094204 | pH | Most enzymes work best at a pH of 7. Other enzymes work at a very low pH such as pepsin, the digestive enzyme which works best in a pH of 2. All enzymes are active over a narrow range of pH. | 13 | |
| 8209094205 | Enzyme Regulation | Enzymes are regulated by changing the shape of the enzyme. | 14 | |
| 8209094206 | Allosteric Sites | They are binding sites other than the active site in which an allosteric regulator can bind to change the shape of the enzyme to either activate it or deactivate it. | 15 | |
| 8209094207 | Allosteric Regulator | They are molecules that bind to the allosteric site on an enzyme to change it's shape. There are two types of regulators, allosteric inhibitors that makes the enzyme inactive and allosteric activator binds to an enzyme and changes its shape to its active form. | 16 | |
| 8209094208 | Feedback Inhibition | It is when the enzyme catalyzes a reaction whose end product that inhibits a previous reaction that involves that enzyme. | 17 | |
| 8209094209 | Competitive Inhibition | It is when a substance that is similar in shape to the substrate is able to bind to the active site of an enzyme and thus prevent it from further binding to substrates. | 18 | |
| 8209094210 | Noncompetitive Inhibition | It is when an inhibitor binds to the enzyme at a site other than the active site and thus changes the shape of the enzyme so that it can no longer bind to substrates. | 19 | |
| 8209094211 | First Law of Thermodynamics | Energy cannot be created or destroyed, the sum of energy in the world is constant. | 20 | |
| 8209094212 | Second Law of Thermodynamics | Energy transfer leads to less organization and the universe tends towards disorder or entropy. | 21 | |
| 8209094213 | Adenosine Triphosphate | It is the "currency" in cells that help make everything run. ATP is ADP + P + energy and thus when the third phosphate is broken off, energy can be released. Cells also store energy in ATP in the phosphate bonds. | 22 |
