UPGRADE: Metabolism Flashcards
(55 cards)
Metabolism
The sum of all chemical reactions in a cell or organism.
Kinetic energy
The energy of motion.
Potential energy
The stored energy that an object possesses as a result of its position relative to other objects or to its internal structure.
The first law of thermodynamics
Principle that states that energy can be transferred or transformed, but it cannot be created or destroyed.
Bond energy
The minimum amount of energy that is required to break a particular type of bond, measured in kJ/mol of bonds.
Mole
The number (approximately 6.022 X 10^23) of atoms or molecules whose mass in grams is equal to the atomic mass of one such particle in atomic mass units; one carbon atom is has a mass of 12 AU, and, therefore, one mole of carbon atoms has a mass of 12 g.
Activation energy
The minimum amount of energy that chemical reactions must absorb to start a reaction.
Transition state
A temporary condition during a chemical reaction in which the bonds in the reactants are breaking and the bonds in the products are forming.
Exothermic reaction
A chemical reaction in which energy is released, leaving the products with less chemical potential energy than the reactants.
Endothermic reaction
A chemical reaction in which energy is absorbed, giving the products more chemical potential energy that than the reactants.
Spontaneous change
A change that will, once begin, continue on its own under a given set of conditions; does not require a continuous supply of energy.
Free energy
Energy that can do useful work; also called Gibbs free energy.
Exergonic reaction
A chemical reaction that releases free energy; the products have less free energy than the reactants.
Endergonic reaction
A chemical reaction that absorbs free energy; the products have more free energy than the reactants.
Energy coupling
The transfer of energy from one reaction to another in order to drive the second reaction.
Catabolic pathway
A pathway in which energy is released and complex molecules are broken down into simple molecules.
Negative ΔG
Anabolic pathway
A pathway in which energy is supplied to build complex molecules from simple molecules.
Positive ΔG
Aerobic cellular respiration
A process that uses oxygen to harvest energy from organic compounds.
Obligate aerobe
An organism that cannot live without oxygen.
Substrate-level phosphorylation
The formation of ATP by the direct transfer of a phosphate group from a substrate to ADP.
Oxidative phosphorylation
A process that forms ATP using energy transferred indirectly that forms ATP using energy transferred indirectly from a series of redox reactions.
Glycolysis
A series of reactions in which a glucose molecules is broken into two pyruvate molecules and energy is released.
Pyruvate oxidation
A reaction in which pyruvate is oxidized by NAD+, and CO2 is removed, forming an acetyl group and releasing NADH.
Citric acid cycle
A cyclic series of reactions that transfers energy from organic molecules to ATP, NADH, and FADH2 and releases carbon atoms as CO2.
