Exam 3 Flashcards
(84 cards)
potential energy
the energy that matter possesses as a result of its location or spatial arrangement (structure)
Kinetic energy
the energy associated with the relative motion of objects. Moving matter can perform work by imparting motion to other matter
first law of thermodynamics
energy can neither be created or destroyed, energy can be converted from one form to another
second law of thermodynamics
disorder is more likely then order, entropy is increasing
all energy transformations proceed
spontaneously, more ordered to a less ordered, more stable to less stable, energy dissipates as heat
heat
random motions of molecules
anabolic pathways
metabolic pathway that consumes energy to synthesize a complex molecule from simpler molecules
catabolic pathways
a metabolic pathway that releases energy by breaking down complex molecules to simpler molecules
free energy
portion of a biological system’s energy that can perform work when temp and pressure are uniform throughout the whole system
activation energy
amount of energy that reactants must absorb before a chemical reaction will start
exergonic reactions
spontanious chemical reaction in which there is a net release of free energy
endergonic reactions
nonspontanious chemical reaction in which free energy is absorbed from the surrondings
Adenosine triphosphate
an adenine-containing nucleoside triphosphate that releases free energy when its phosphate bonds are hydrolized. used to drive endergonic reactions
3 components of ATP
ribose, adenine, and phosphate groups
redox reactions
chemical reaction involving the complete or partial transfer of one or more electronsfrom one reactant to another
enzymes
macromolecule serving as a catalyst, chemical agent that increases the rate of reaction without being consumed by the reaction. most are proteins
coenzymes
organic molecule serving as a cofactor. most vitamins function as coenzymes in metabolic reactions
enzyme-substrate complex
temporary complex formed when an enzyme binds to its substrate molecule
active site
specific of an enzyme that binds the substrate and that forms the pocket in which catalysis occurs
four stages of aerobic respiration
glycolysis, pyruvate oxidation, krebs cycle, and electron transport chain and chemiosmosis
glycolysis
breaks down glucose and forms pyruvate with the production of two molecules of ATP
krebs cycle
series of chemical reactions, releases stored energy through the oxidation of acetyl-CoA derived from carbohydrates, fats and proteins into carbon dioxide and ATP
electron transport chain
compounds that transfer electrons from electron donors to electron acceptors via redox reactions, and couples this electron transfer with the transfer of protons (H+ ions) across a membrane.
where does glycolysis occur
cytoplasam