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| the total of an organism's chemical reactions; an emergent property of life that arises from interactions between molecules within the orderly environment of the cell | ||
| begins with a specific molecule, which is then altered in a series of defined steps, resulting in a specific product; each step of teh pathway is catalyzed by a specific enzyme | ||
| a metabolic process that breaks down complex molecules into simpler compounds; example = cellular respiration because it breaks glucose into carbon dioxide and water; the energy that is stored becomes available to do work within the cell | ||
| a metabolic process that consumes energy to build complicated molecules from simpler molecules; example = synthesis of a protein from amino acids; energy comes from catabolic pathways | ||
| the study of how energy flows through living organisms | ||
| the capacity to cause change | ||
| the relative motion of an object | ||
| kinetic energy associated with random movement of atoms or molecules | ||
| the energy that matter possesses because of its location or structure when it is at rest; due to arrangement of atoms | ||
| the type of energy that refers to the potential energy available for release in a chemical reaction; glucose, for example, has a high amount of this | ||
| the study of energy transformations that occur in a collection of matter | ||
| a rule that states that the energy of the universe is constant; energy can be transferred and transformed, but it cannot be created or destroyed | ||
| a rule that states that every energy transfer or transformation increases the entropy (disorder) of the universe; unstoppable trend toward randomization of the universe as a whole | ||
| the portion of a system's energy that can perform work when temperature and pressure are uniform throughout the system, as in a living cell; this type of energy is a measure of a system's instability, meaning its tendency to change to a more stable state | ||
| disorder of the universe | ||
| order of the universe | ||
| the variable of free energy that represents a generally unstable system | ||
| the variable of free energy that represents a generally stable system | ||
| the type of reaction that proceeds with a net release of free energy; because the chemical mixture loses free energy, Gibbs free energy is negative; it is a spontaneous reaction | ||
| the type of reaction that absorbs free energy from surroundings; because energy is stored in molecules, Gibbs free energy is positive; the reaction is nonspontaneous | ||
| the type of cellular work that includes the pushing of endergonic reactions, which would not occur spontaneously, such as the synthesis of polymers from monomers | ||
| the type of cellular work that includes the pumping of substances across membranes against the direction of spontaneous movement | ||
| the type of cellular work that includes the beating of cilia, the contraction of muscle cells, and the movement of chromosomes during reproduction | ||
| the use of an exergonic process to drive an endergonic one; ATP is responsible for mediating this, and it acts as an energy source | ||
| this molecule is composed of ribose, adenine, and a chain of three phosphate groups | ||
| the state of a molecule when it receives a phosphate, such as in ATP hydrolysis, making it more reactive (less stable) than the original molecule | ||
| a macromolecule that acts as a catalyst; without this, pathways of metabolism would be congested because reactions would take so long | ||
| a chemical agent that speeds up a reaction without being consumed by the reaction; enzymes are examples of these | ||
| the initial investment of energy for starting a reaction; the energy required to destabilize the reactant molecules so their bonds can break; also, the amount of energy needed to push reactants over a "hill" so that the "downhill" part of the reaction can begin | ||
| the reactant an enzyme acts on | ||
| the entity that forms when an enzyme bonds to a substrate, in which the enzyme's catalytic reaction converts the substrate to the product of the reaction | ||
| a pocket or groove on the surface of an enzyme where catalysis occurs; there is only one of these per enzyme; this is formed by a few amino acids while others construct a frame for it | ||
| a molecule in a metabolic pathway that is a product in one step and used as a reactant in another step; it can be crossed out from the overall equation | ||
| the equation for the hydrolysis of ATP | ||
| the amount of Gibbs free energy that results from the hydrolysis of ATP | ||
| the equation for the synthesis of ATP | ||
| the amount of Gibbs free energy that results from the synthesis of ATP | ||
| the equation for aerobic cellular respiration | ||
| the amount of Gibbs free energy that results from aerobic cellular respiration | ||
| in this step of catalysis, the substrate enters the active site; the enzyme changes shape so the active site can enfold the substrate | ||
| in this step of catalysis, the substrate and enzyme bond via weak bonds | ||
| in this step of catalysis, the active site lowers the activation energy for the reaction | ||
| doing these things: a) acting as a template for substrate orientation, b) stressing the substrates and stabilizing the transition state, c) providing a favorable microenvironment, and d) participating directly in catalytic reaction, are ways to do what in a reaction? | ||
| the state that an enzyme is said to be in if as soon as the product of one reaction leaves, a new substrate enters the active site | ||
| nonprotein helpers for catalytic reactions; these may be bound tightly to an enzyme as a permanent resident, or may be bound loosely and reversibly along the substrate | ||
| cofactors that are inorganic; examples of these are vitamins | ||
| chemicals that selectively reduce or prevent the action of a specific enzyme | ||
| reversible inhibitors that resemble the normal substrate molecule and compete for admission into the active site; these reduce productivity by blocking substrates from entering active sites; these can be overcome by producing more substrates to outnumber them; poisons are an example of these with strong bonds | ||
| this occurs when a molecule that resembles substrate bonds to the active site, thereby blocking the substrate; this occurs with weak bonds; the higher the concentration of the inhibitor, the slower the reaction; not used intentionally | ||
| these molecules do not directly compete with substrates--instead, they bind to another part of the enzyme, causing it to change its shape so that the active site becomes less effective at conversion | ||
| this occurs when a molecule bonds to some other location on an enzyme, causing a conformational change, which blocks the active site; after the molecule leaves, however, the enzyme returns to its original shape; may result in either inhibition or enhanced activity of an enzyme | ||
| the alternate location on an enzyme where noncompetitive inhibitors bond | ||
| a -G with the addition of a catalyst ________________ the reaction | ||
| a -G with no addition of a catalyst ________________ the reaction | ||
| a +G coupled with an exergonic reaction and with the addition of a catalyst ____________ the reaction | ||
| a +G without a coupled reaction and without a catalyst ________________ the reaction | ||
| the change in G for an exergonic reaction (energy outward) | ||
| the change in G for an endergonic reaction (energy inward) | ||
| the state of a reaction at which just enough energy is reached to break the bonds of reactants | ||
| a mechanism that amplifies the response of an enzyme to a substrate by leading one substrate molecule to prime an enzyme's acceptance of additional substrate molecules; when one subunit of an enzyme has an induced fit, other subunits mimic that fit; example = hemoglobin: as soon as one oxygen bonds to a heme group within the polypeptide chain of hemoglobin, the other three polypeptide chains develop a greater affinity to oxygen | ||
| an occurrence in which a metabolic pathway is switched off by the inhibitory binding of its end product to an enzyme that acts early in the pathway; this prevents the cell from wasting chemical resources; when an end product stops or slows its own production | ||
| where enzymes for cellular respiration are found within a cell | ||
| the model for enzymes that says that enzymes are highly specific, and as a result, there is only one substrate that fits in an enzyme's active site; criticism: because proteins can be denatured, it is somewhat unlikely that rigid guidelines can be followed exactly | ||
| the model for enzymes that says that as the substrate and active site approach each other, each influences the other's shape so they mold together; compared to a proper handshake: both entities conform to make a good grip in order to interact | ||
| 1) molecules must collide, 2) molecules must collide with sufficient energy, 3) molecules must collide with proper orientation | ||
| optimal temperature range for enzymes in the human body (in degrees Celsius) | ||
| optimal pH range for enzymes in the human body |
