AP bio unit 3
ATP (adenosine triphosphate) main energy source that cells use for most of their work
ADP adenosine diphosphate; molecule that ATP becomes when it gives up one of its three phosphate groups
Free Energy Chemical energy available to do work
Autotroph An organism that is capable of living exclusively on inorganic materials, water, and an energy source other than the chemical bonds of organic compounds. Some autotrophs (photoautotrophs) use sunlight as their energy source. Others (chemoautotrophs) use oxidation of inorganic compounds.
Heterotroph An organism that requires preformed organic molecules as sources of energy and chemical building blocks.
Metabolism The sum of the building & breaking reactions occurring in cells
Catabolic Pathways Series of reactions that release energy by breaking down complex molecules into simpler compounds.
Anabolic Pathways Series of reactions that consume energy to build complicated molecules from simpler ones.
Phosphorylation the enzyme-mediated direct transfer of phosphate from another molecule (the substrate) to ADP
Oxidation Relative loss of electrons in a chemical reaction; either outright removal to form an ion, or the sharing of electrons with substances having a greater affinity for them, such as oxygen. Most oxidations, including biological ones, are associated with the liberation of energy.
Reduction Gain of electrons by a chemical reactant; any reduction is accompanied by an oxidation.
NAD+ nicotinamide adenine dinucleotide - a coenzyme that is an electron carrier; NAD+ is oxidized, NADH is reduced
FAD
Cellular Respiration The catabolic pathways by which electrons are removed from various molecules and passed through intermediate electron carriers to O2, generating H2O and releasing energy.
Aerobic Respiration Requiring molecular oxygen, O2
Anaerobic Respiration Occurring without the use of molecular oxygen, O2.
Glycolysis
Pyruvate Three-carbon compound that forms as an end product of glycolysis.
Endergonic Reaction that absorbs free energy from its surroundings.
Exergonic Reaction that proceeds with a net release of free energy.
Alcohol Fermentation Anaerobic series of reactions that convert glucose to ethyl alcohol (ethanol) and carbon dioxide in some plants and yeast cells.
Lactic Acid Fermentation Anaerobic series of reactions that convert glucose to ethyl alcohol (ethanol) and carbon dioxide in some plants and yeast cells.
Krebs Cycle In cellular respiration, a set of chemical reactions whereby acetyl CoA is oxidized to carbon dioxide and hydrogen atoms are stored as NADH and FADH2. Also called the Krebs cycle.
Photosynthesis Metabolic processes carried out by green plants and cyanobacteria, by which visible light is trapped and the energy used to convert CO2 into organic compounds.
Light Reactions The initial phase of photosynthesis, in which light energy is converted into chemical energy.
Chlorophyll Any of several green pigments associated with chloroplasts or with certain bacterial membranes; responsible for trapping light energy for photosynthesis.
Absorption Spectrum A graph of light absorption versus wavelength of light; shows how much light is absorbed at each wavelength.
Action Spectrum A graph of a biological process versus light wavelength; shows which wavelengths are involved in the process.
Light-Harvesting Complex in photosynthesis, a group of different molecules that cooperate to absorb light energy and transfer it to a reaction center. Also called antenna system.
Photosystem A light-harvesting complex in the chloroplast thylakoid composed of pigments and proteins.
Calvin Cycle is a series of enzyme-assisted chemical reactions that produces a three-carbon sugar
Enzyme Protein that speeds up reactions. Typically end in "ase" (ex. Peroxidase, Lipase)
Catalyst A chemical agent that speeds up a reaction without being consumed by the reaction.
Activation Energy The amount of energy needed to push the reactants over an energy barrier.
Enzyme-Substrate Complex When an enzyme binds to its substrate
Active Site A pocket or groove on the surface of the enzyme where a substrate can bind.
Induced Fit Model States that the enzyme and substrate undergo conformational changes to interact fully with one another (as opposed to "Lock & Key")
Competitive Inhibitors Reduce the productivity of enzymes by blocking substrates from entering active sites.
Noncompetitive Inhibitors Impede enzymatic reactions by binding to another part of the enzyme (other than the active site).
Saturated Enzyme Describes an enzyme's maximum activity when every active site is being used.
Denaturation Characteristic of proteins; a change in shape that stops the protein from functioning.