Chapter 8: An Introduction to Metabolism Flashcards
Amount of energy that reactants must absorb before a chemical reaction will start; also called free energy of activation
Activation Energy
Specific region of an enzyme that binds the substrate and that forms the pocket in which catalysis occurs
Active Site
The binding of a regulatory molecule to a protein at one site that affects the function of the protein at a different site
Allosteric Regulation
A metabolic pathway that consumes energy to synthesize a complex molecule from simpler molecules
Anabolic Pathway
An adenine-containing nucleoside triphosphate that releases free energy when its phosphate bonds are hydrolyzed. This energy is used to drive endergonic reaction in cells
ATP (Adenosine Triphosphate)
A metabolic pathway that releases energy by breaking down complex molecules to simpler molecules
Catabolic Pathway
Process by which chemical agent called a catalyst selectively increases the rate of reaction without being consumed by the reaction
Catalysis
A chemical agent that speeds up the rate of reaction without being consumed by the reaction
Catalyst
Energy available in molecules release in a chemical reaction; form of potential energy
Chemical Energy
An organic molecule serving as a co-factor. Most vitamins function as co-enzymes in metabolic reactions
Co-Enzyme
Any nonprotein molecule or ion that is required for the proper functioning of an enzyme. Can be permanently bound to the active site or may bind loosely and reversibly, along with the substrate, during catalysis
Co-Factor
A substance that reduces the activity of an enzyme by entering the active site in place of the substrate, whose structure mimics
Competitive Inhibitor
A kind of allosteric regulation whereby a shape change in one subunit of a protein caused by substrate binding is transmitted to all the other subunits, facilitating binding of additional substrate molecules to those subunits
Cooperativity
Non-spontaneous chemical reaction in which free energy is absorbed from the surroundings
Endergonic Reaction
Capacity to cause change. Ability to rearrange a collection of matter
Energy
A measure of molecular disorder or randomness
Entropy
Macromolecule that acts as a catalyst, a chemical agent that speeds up the rate of reaction without being consumed by the reaction
Enzyme
A temporary complex formed when an enzyme binds to its substrate molecule
Enzyme‐Substrate Complex
Spontaneous chemical reaction in which there is net release of free energy
Exergonic Reaction
A method of metabolic control in which the end product of metabolic pathway acts as an inhibitor of an enzyme within that pathway
Feedback Inhibition
Principle of conversion of energy, energy can be transferred or transformed, but cannot be created or destroyed
First Law of Thermodynamics
The portion of a biological system’s energy that can perform work when temperature and pressure are uniform throughout the system
Free Energy
Series of chemical reactions that either builds a complex molecule (anabolic pathway) or breaks down a complex molecule to simpler molecules (catabolic pathway)
Metabolic Pathway
The totality’s of an organisms chemical reactions, consisting of catabolic and anabolic pathways, which manage the material and energy resources of the organism
Metabolism
A substance that reduces the activity of an enzyme by binding to a location remote from the active site, changing the enzyme’s shape so that the active site no longer effectively catalyzes the conversion of substrate to product
Non-Competitive Inhibitor
Molecule with a phosphate group covalently bound to it, making it more reactive (less stable) than the unphosphorylated molecule
Phosphorylated Intermediate
Principle stating that every energy transfer or transformation increases the entropy of the universe. Usable forms of energy are at least party converted to heat
Second Law of Thermodynamics
A process that occurs without energy; process that is energetically favorable
Spontaneous Process
The reactant on which an enzyme works with
Substrate
Study of energy transformations that occur in a collection of matter; 2 laws
Thermodynamics
