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| All of an organisms chemical reactions. Arises from interaction between molecules within the environment of the cells of an organism. Manages the material and energy resources of cells. |
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| The thousands of chemical reactions that occur in the cell. Begins with a specific molecule which is then changed in a series of defined steps and which results in a certain product. Eac hstep along the way is catalyzed by a specific enzyme. There is a constant balance of suppy and demand. Can be anabolic or catabolic. |
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| Metabolic pathways that breakdown molecules and release energy. Cellular respiration provides energy for cellular activites like cell membrane transport. Pathways can have more than one starting material and/or product. |
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| Metabolic pathways which consume energy and build complicated molecules. Also called biosynthetic pathways. Synthesis of proteins from amino acids is an example. |
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| The study of how organisms manage their energy resaources. |
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| The capacity to cause change or do work. The ability to rearrange a collection of matter. It exists in various forms. It can be transformed into another form. |
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| The energy associated with the relative motion of objects. |
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| The kinetic energy associated with the random movement of atoms or molecules. |
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| The energy in an object not presently moving based on its location and/or structure. Water behind a dam is an example. |
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| The potential energy available for release in a chemical reaction. |
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| The study of energy transformations in a collection of matter. |
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| The matter under study in thermodynamics. |
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| Everything outside the system in an experiment on thermodynamics. |
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| The system is isolated from its surroundings. Think liquid in a thermos. |
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| Energy can be transferred between the system and its surroundings. Organisms are open systems. They can absorb and/or releae energy from/to their surroundings. |
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| First Law of Thermodynamics |
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| The energy of the universe is constant. Energy can be tranferred and transformed but it cannot be created or destroyed. Also called the Principle of Conservation of Energy. |
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| A measure of disorder or randomness. The more randomly arrranged a collection of matter is the greater its entropy. |
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| The Second Law of Thermodynamics |
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| Every energy transfer or transformation increases the entropy of the universe. There is an unstoppable trend toward randomization of the universe as a whole. |
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| Measures the portion of a systems energy that can perform work when temperature and pressure are uniform throughout the system. Called delta G. Can be calculated for any specific chemical reaction. The measure of a systems instability. |
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| Change in free energy = total energy - temperature times the change in the systems entropy. |
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| Have a negative delta G, or free energy. |
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| A reaction that proceeds with a release of free energy. The reaction has a negative delta G and is therefore a spontaneous reaction. |
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| A reaction that absorbs energy from its surroundings. It has a positive delta G and are therefore not spontaneous. |
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| The point at which a reaction in a closed system can no longer perform work. Cells do not reach equalibrium. |
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| Can be mechanical, transport or chemical. |
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| Contraction of muscle cells, movement of chromosomes during cell reproduction. |
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| The movement of molecules scross a cell membrane against the gradient. |
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| Pushing of endergonic reactions which are not spontaneous. |
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| Adenosine TriPhosphate. Contains the sugar ribose, with adenine and a side chain of three phosphate groups. Phosphate can be removed by water in a hydrolysis reaction which releases energy. A re-newable resource. |
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| The trnasfer of a phosphate from ATP to another molecule. |
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| A chemical agent that speeds up a reaction without being consumed by the reaction. An enzyme is a catalyst. |
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| A catalyst which speeds up a chemical reaction without being consumed in the reaction. Very reaction specific. |
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| Also called the free energy of activation. The initial investment of energy for starting a reaction. The amount of energy needed to push the reactants over the enrgy barrier. Abbreviated E sub A. Often supplied in the form of heat. |
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| The summit of a reaction where the reactants are in their most unstable condition just prior to a reaction occuring. |
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| The reactant and enzyme acts on . The enzyme binds to it forming an enzyme-substrate complex. |
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| When an enzyme is bound to a specific substrate just prior to the reaction occuring which will form the junchanged enzyme and a new product. |
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| A restricted region of the enzyme molecule binds to a substrate. A pocket or groove on the surface of the enzyme specific to a particular substrate. What determines the specificity of the enzyme for a substrate. |
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| A change in the shape of an enzymes active site when the substrate bonds to it. This allows the substrate to sit even more snuggly into the enzyme so the reaction can occur. |
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| A non-protein "helper" which helps catalyze an enzymes action. May be bound to the enzyme permanently or it may bind loosely and reversibly with the substrate. |
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| The name for an organic molecule that acts as a cofactor in an enzymatic reaction. Vitamins are coenzymes. |
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| Reduce the productivity of enzymes by binding to the active site either reversibly or irreversibily.. It can be overcome by increasing the amount of actual substrate. Toxins and poisons are often irreversible inhibitors. |
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| Non-competitive Inhibition |
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| Molecules which do not directly compete with the substrate for an enzymes active site. They bind to another site on the enzyme causing the enzyme to change shape rendering the active site less functional. |
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| When a molecule binds to a one site on an enzyme which affects the function of another site on the same enzyme either inhibiting or enhancing the proteins function. |
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| A molecule which binds to an allosteric site on an enzyme which stabilizes the more active form of the enzyme. |
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| A molecule which binds to an enzymes allosteric state and stbilizes it in the inhibited state. |
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| Amplifies the response of an enzyme to a substrate. When one substrate molecule primes an enzyme to accept another substrate molecule more readily. When an enzyme has 2, or more, subunits. |
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| A common form of metabolic control. When a metabolic pathway is switched off by an inhibitory binding of its end product early in its pathway. |
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