AP Bio unit 3 (cooler and better)

Metabolic pathway

A series of chemical reactions in a cell that lead to a specific product.

Catabolic pathway

A metabolic pathway that breaks down molecules into smaller units, releasing energy.

Anabolic pathway

A metabolic pathway that builds larger molecules from smaller units, requiring energy.

Potential energy

Stored energy that has the potential to do work.

Chemical energy

Energy stored in the bonds of chemical compounds.

Free energy (∆G)

The energy available to do work in a system at constant temperature and pressure.

Exergonic reaction

A reaction that releases energy, typically in the form of heat.

Endergonic reaction

A reaction that absorbs energy from its surroundings.

ATP (adenosine triphosphate)

The primary energy carrier in cells.

Enzyme

A biological catalyst that speeds up a chemical reaction.

Catalyst

A substance that increases the rate of a chemical reaction without being consumed.

Activation energy

The minimum energy required to initiate a chemical reaction.

Substrate

The reactant molecule upon which an enzyme acts.

Enzyme substrate-complex

The temporary complex formed when an enzyme binds to its substrate.

Active site

The specific region of an enzyme where the substrate binds.

Induced fit

The change in shape of an enzyme when it binds to its substrate.

Cofactors

Non-protein molecules that assist enzymes in catalyzing reactions.

Coenzymes

Organic cofactors that are required for enzyme activity.

Competitive inhibitors

Substances that compete with the substrate for binding to the active site of an enzyme.

Noncompetitive inhibitors

Substances that bind to an enzyme at a site other than the active site, reducing its activity.

Fermentation

A metabolic process that converts sugar to acids, gases, or alcohol in the absence of oxygen.

Aerobic respiration

A process that requires oxygen to convert glucose into ATP.

Cellular respiration

The process by which cells convert glucose and oxygen into energy, carbon dioxide, and water.

Redox reaction

A chemical reaction involving the transfer of electrons between two species.

Oxidation

The loss of electrons from a substance.

Reduction

The gain of electrons by a substance.

Electron carrier

Molecules that transport electrons during cellular respiration.

NAD+/NADH

A coenzyme that acts as an electron carrier in cellular respiration.

Glycolysis

The metabolic pathway that converts glucose into pyruvate, producing ATP.

Pyruvate oxidation

The process that converts pyruvate into acetyl-CoA, releasing CO2 and producing NADH.

Citric acid cycle (Krebs cycle)

A series of chemical reactions used by all aerobic organisms to generate energy.

Electron Transport Chain

A series of protein complexes that transfer electrons and pump protons to create a proton gradient.

Chemiosmosis

The movement of ions across a selectively permeable membrane, down their electrochemical gradient.

Substrate-level phosphorylation

The direct transfer of a phosphate group to ADP to form ATP during glycolysis and the citric acid cycle.

Oxidative phosphorylation

The production of ATP using energy derived from the redox reactions of the electron transport chain.

ATP synthase

An enzyme that creates ATP from ADP and inorganic phosphate during chemiosmosis.

Proton motive force

The potential energy stored in the form of a proton gradient across a membrane.

Alcohol fermentation

A process by which sugars are converted into alcohol and carbon dioxide by yeast.

Lactic acid fermentation

A process by which sugars are converted into lactic acid by bacteria or muscle cells.

Photosynthesis

The process by which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll.

Autotrophs

Organisms that produce their own food from inorganic substances.

Heterotrophs

Organisms that obtain their food by consuming other organisms.

Chloroplast

An organelle found in plant cells that conducts photosynthesis.

Mesophyll

The inner tissue of a leaf where photosynthesis occurs.

Stomata

Small openings on the surface of leaves that allow gas exchange.

Stroma

The fluid-filled space inside chloroplasts where the Calvin cycle occurs.

Thylakoids

Membrane-bound compartments inside chloroplasts that contain chlorophyll.

Chlorophyll

The green pigment found in plants that is essential for photosynthesis.

NADP+/NADPH

A coenzyme that carries electrons during photosynthesis.

Photophosphorylation

The process of converting light energy into chemical energy in the form of ATP.

Wavelength

The distance between successive peaks of a wave, often related to light.

Photon

A particle of light that carries energy.

Absorption spectrum

A spectrum of absorbed light by a pigment.

Chlorophyll a

The primary pigment involved in photosynthesis.

Chlorophyll b

An accessory pigment that assists in photosynthesis.

Carotenoids

Pigments that provide color to plants and assist in photosynthesis.

Light reactions

The first stage of photosynthesis where light energy is converted into chemical energy.

Photosystem

A complex of proteins and pigments that captures light energy for photosynthesis.

Reaction center complex

The part of a photosystem that converts light energy into chemical energy.

Light-harvesting complex

A group of proteins and pigments that capture light energy and funnel it to the reaction center.

Primary electron acceptor

The first molecule that accepts an electron from the reaction center of a photosystem.

Photosystem II (PSII)

The first photosystem in the light reactions of photosynthesis.

Photosystem I (PSI)

The second photosystem in the light reactions of photosynthesis.

Linear electron flow

The flow of electrons through the electron transport chain in a linear pathway.

Cyclic electron flow

The flow of electrons in a cyclic pathway that generates ATP without producing NADPH.

Light independent reactions/Calvin cycle

The set of reactions in photosynthesis that do not require light and produce glucose.

Carbon fixation

The process of converting inorganic carbon (CO2) into organic compounds.

Rubisco

An enzyme that catalyzes the first step of carbon fixation in the Calvin cycle.

Reduction

The process of gaining electrons or hydrogen ions.

G3P

Glyceraldehyde-3-phosphate, a three-carbon sugar produced in the Calvin cycle.

Regeneration of RuBP

The process of regenerating ribulose bisphosphate in the Calvin cycle.

C3 Plants

Plants that fix carbon dioxide directly through the Calvin cycle.

Photorespiration

A process that consumes oxygen and releases carbon dioxide, occurring in plants.

C4 Plants

Plants that fix carbon dioxide into a four-carbon compound before the Calvin cycle.

CAM Plants

Plants that open their stomata at night to fix carbon dioxide. Metabolic pathway

Catabolic pathway

A metabolic pathway that breaks down molecules into smaller units, releasing energy.

Anabolic pathway

A metabolic pathway that builds larger molecules from smaller units, requiring energy.

Potential energy

Stored energy that has the potential to do work.

Chemical energy

Energy stored in the bonds of chemical compounds.

Free energy (∆G)

The energy available to do work in a system at constant temperature and pressure.

Exergonic reaction

A reaction that releases energy, typically in the form of heat.

Endergonic reaction

A reaction that absorbs energy from its surroundings.

ATP (adenosine triphosphate)

The primary energy carrier in cells.

Enzyme

A biological catalyst that speeds up a chemical reaction.

Catalyst

A substance that increases the rate of a chemical reaction without being consumed.

Activation energy

The minimum energy required to initiate a chemical reaction.

Substrate

The reactant molecule upon which an enzyme acts.

Enzyme substrate-complex

The temporary complex formed when an enzyme binds to its substrate.

Active site

The specific region of an enzyme where the substrate binds.

Induced fit

The change in shape of an enzyme when it binds to its substrate.

Cofactors

Non-protein molecules that assist enzymes in catalyzing reactions.

Coenzymes

Organic cofactors that are required for enzyme activity.

Competitive inhibitors

Substances that compete with the substrate for binding to the active site of an enzyme.

Noncompetitive inhibitors

Substances that bind to an enzyme at a site other than the active site, reducing its activity.

Fermentation

A metabolic process that converts sugar to acids, gases, or alcohol in the absence of oxygen.

Aerobic respiration

A process that requires oxygen to convert glucose into ATP.

Cellular respiration

The process by which cells convert glucose and oxygen into energy, carbon dioxide, and water.

Redox reaction

A chemical reaction involving the transfer of electrons between two species.

Oxidation

The loss of electrons from a substance.

Reduction

The gain of electrons by a substance.