AP Bio Chapter 8 - Intro to Metabolism
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| 924415543 | metabolism | the totality of an organism's chemical reactions | 1 | |
| 924415544 | catabolic pathway | a metabolic process that breaks down complex molecules into simpler compounds |  | 2 |
| 924415545 | anabolic pathway | a metabolic process that consumes energy to build complicated molecules from simpler ones |  | 3 |
| 924415546 | energy | the capacity to cause change | 4 | |
| 924415547 | kinetic energy | the relative motion of an object | 5 | |
| 924415548 | heat energy | kinetic energy associated with random movement of atoms or molecules | 6 | |
| 924415549 | potential energy | the energy that matter possesses because of its location or structure when it is at rest; due to arrangement of atoms | 7 | |
| 924415550 | chemical energy | the type of energy that refers to the potential energy available for release in a chemical reaction |  | 8 |
| 924415551 | first law of thermodynamics | 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 | 9 | |
| 924415552 | second law of thermodynamics | 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 | 10 | |
| 924415553 | free energy | 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 | 11 | |
| 924415554 | entropy | disorder of the universe | 12 | |
| 924415555 | exergonic | 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 |  | 13 |
| 924415556 | endergonic | 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 |  | 14 |
| 924415557 | chemical work | the type of cellular work that includes the pushing of endergonic reactions, which would not occur spontaneously, such as the synthesis of proteins from amino acids |  | 15 |
| 924415558 | transport work | the type of cellular work that includes the pumping of substances across membranes against the direction of spontaneous movement |  | 16 |
| 924415559 | mechanical work | the type of cellular work that includes the beating of cilia, the contraction of muscle cells, and the movement of chromosomes during reproduction |  | 17 |
| 924415560 | energy coupling | the use of an exergonic process to drive an endergonic one; ATP is responsible for mediating this, and it acts as an energy source |  | 18 |
| 924415561 | ATP | this energy molecule for the cell is composed of ribose, adenine, and a chain of three phosphate groups |  | 19 |
| 924415562 | phosphorylated | the state of a molecule when it receives a phosphate, such as in synthesis of ATP from ADP + inorganic phospate, making it more reactive (less stable) than the original molecule |  | 20 |
| 924415563 | enzyme | a macromolecule that acts as a catalyst; without this, pathways of metabolism would be congested because reactions would take so long |  | 21 |
| 924415564 | catalyst | a chemical agent that speeds up a reaction without being consumed by the reaction; enzymes are examples of these | 22 | |
| 924415565 | activation energy | 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 |  | 23 |
| 924415566 | substrate | the reactant an enzyme acts on | | 24 |
| 924415567 | enzyme-substrate complex | 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 | 25 | |
| 924415568 | active site | a pocket or groove on the surface of an enzyme where where the substrate docks up and catalysis occurs | | 26 |
| 924415569 | ATP --> ADP + P(i) | the equation for the hydrolysis of ATP | 27 | |
| 924415570 | -7.3 kcal/mol | the amount of Gibbs free energy that results from the hydrolysis of ATP | 28 | |
| 924415571 | ADP + P(i) --> ATP + H2O | the equation for the synthesis of ATP | 29 | |
| 924415572 | cofactors | 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 |  | 30 |
| 924415573 | coenzyme | cofactors that are organic; examples of these are vitamins | 31 | |
| 924415574 | competitive inhibition | 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 |  | 32 |
| 924415575 | noncompetitive inhibitors | 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 |  | 33 |
| 924415576 | allosteric regulation | 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 |  | 34 |
| 924415577 | -G | the change in G for an exergonic reaction (energy yeilding) | 35 | |
| 924415578 | +G | the change in G for an endergonic reaction (energy consuming) | 36 | |
| 924415579 | feedback inhibition | 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 |  | 37 |
| 924415580 | lock-and-key | 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 | 38 |
