Unit 3 concept 1

Comprehensive vocabulary flashcards covering metabolic reactions, chemical reaction energetics, enzyme function and kinetics, 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, where breaking bonds requires energy absorption and forming bonds releases energy.

Law of conservation of energy

The scientific principle stating that no energy in the system is lost during chemical reactions; it only changes forms, such as being released as heat or light.

Catabolic reactions

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

Anabolic reactions

Biochemical 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 (substrate)

Substances that are changed during a chemical reaction.

Products

Substances that are made by a chemical reaction.

Endothermic reaction

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

Exothermic reaction

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

Photosynthesis

An endothermic biochemical reaction ($6CO_2 + 6H_2O \rightarrow C_6H_{12}O_6 + 6O_2$) where light energy is stored as chemical energy in sugar.

Cellular Respiration

An exothermic biochemical reaction ($C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O$) where chemical energy in sugar is converted and released as ATP.

Enzymes

Substances (mostly proteins) that speed up biochemical reactions by lowering activation energy without being permanently altered or used up.

Catalysts

Substances that speed up reactions without being permanently altered by lowering the activation energy needed for the reaction to start.

Active site

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

Induced fit

The slight conformational tightening or change in shape of an enzyme as a substrate binds to its active site.

Denaturation

The loss of an enzyme's biological activity caused by its active site becoming deformed and losing its specific shape due to extreme environmental changes such as pH, temperature, ion strength, and solubility.

Competitive inhibitor

A substance that slows down a chemical reaction by directly competing with the substrate for the enzyme's active site.

Substrate Concentration

A factor influencing reaction rate where a higher amount of substrate increases the reaction speed due to an increased frequency of particle collisions.

Temperature (reaction rate)

A factor influencing reaction rate where an increase causes molecules to move faster and collide more frequently, speeding up the reaction.

pH

A measure of how acidic a solution is; changes in pH can alter reaction rates because most enzymes function only within a very specific pH range.