Day 2-Caracteristics of Life and Enzyme Function Vocabulary

Vocabulary flashcards covering the characteristics of living organisms, enzyme function, activation energy, metabolic reactions, and inhibition mechanisms.

Organism

A complete living thing that possesses all essential characteristics of life.

Irritability

The characteristic of an organism that allows it to respond to a stimulus in its environment.

Homeostasis

The maintenance of a stable internal environment in an organism, such as humans maintaining a body temperature around $98.6^{\text{o}}\text{F}$.

Macromolecules

Large, complex molecules that make up the complex chemistry of living organisms.

Enzyme

A specialized protein that acts as a biological catalyst to speed up chemical reactions in the body by lowering activation energy without being consumed in the process.

Catalyst

A substance that speeds up a chemical reaction without undergoing permanent chemical change or being used up.

Coenzyme

A helper molecule, such as a vitamin, that an enzyme may require to catalyze a specific chemical reaction.

Catabolism

The metabolic pathway involving the breaking down of complex molecules into simpler ones.

Anabolism

The metabolic pathway involving the building of complex molecules from simpler ones.

Activation Energy ($E_a$)

The minimum amount of energy required for a chemical reaction to start.

Exothermic Reaction

A chemical reaction that releases energy through the breaking of chemical bonds, such as a catabolic reaction.

Endothermic Reaction

A chemical reaction that absorbs energy through the formation of chemical bonds, such as an anabolic reaction.

Denaturation

The process in which extreme temperature or pH breaks chemical bonds holding an enzyme together, causing it to lose its tertiary structure and functionality.

Lock and Key Model

A model of enzyme action asserting that the enzyme's active site is perfectly complementary in shape to its specific substrate.

Induced Fit Model

A model of enzyme action in which the enzyme changes the shape of its active site slightly as the substrate binds to achieve a better fit.

Optimal pH

The specific pH level at which a given enzyme functions most efficiently depending on its environment.

Competitive Inhibitor

A molecule that binds directly to the active site of an enzyme, preventing substrate binding and enzyme-substrate complex formation.

Non-Competitive Inhibitor

A molecule that binds to an allosteric site on an enzyme, altering the shape of the active site so that substrates cannot be catalyzed.

Allosteric Site

A site on an enzyme distinct from the active site where non-competitive inhibitors bind.