Enzymes and Biochemical Reactions

Vocabulary practice flashcards covering biochemical reactions, metabolic pathways, enzyme mechanics, denaturation, and factors influencing reaction rates.

Metabolism

All of the chemical reactions within each cell of an organism that provide energy for life's processes and create key molecules.

Chemical reactions

The breaking and forming of bonds between different substances during chemical changes.

Catabolic reactions

Reactions that break down larger molecules into simpler compounds, resulting in a release of energy (exergonic).

Anabolic reactions

Reactions that build larger molecules from smaller ones, requiring the consumption of energy (endergonic).

Activation energy

The amount of energy needed to make a chemical reaction start.

Reactants

Substances that are changed during a chemical reaction (also referred to as substrates).

Products

Substances that are made by a chemical reaction.

Endothermic reaction

A reaction that absorbs energy in the form of heat or light, resulting in more energy stored in the products than in the reactants.

Exothermic reaction

A reaction that releases energy in the form of heat or light, resulting in less energy remaining in the products than in the reactants.

Photosynthesis

An endothermic reaction with the equation $6CO_2 + 6H_2O \rightarrow C_6H_{12}O_6 + 6O_2$, in which light energy is stored as chemical energy in sugar.

Cellular Respiration

An exothermic reaction with the equation $C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O$, in which chemical energy in sugar is converted and released as ATP.

Enzymes

Specialized macromolecules, mostly proteins, that speed up biochemical reactions by lowering the activation energy without being changed or consumed.

Catalysts

Substances that speed up reactions without being permanently altered.

Active site

A specialized region on an enzyme that uniquely fits and binds to only one specific substrate (reactant).

Induced fit

The process by which an enzyme's active site changes shape slightly and tightens its bond once the substrate connects.

Denaturation

A structural deformation where an enzyme's active site loses its specific shape due to environmental changes, causing a loss of biological activity.

Substrate Concentration

The quantity of substrate present in a reaction; higher concentrations increase the reaction rate due to a greater frequency of particle collisions.

Competitive Inhibitor

A substance that slows down a chemical reaction by competing directly with the substrate for binding at the active site on the enzyme.