Cellular Energy and Metabolism Review

These flashcards summarize key concepts of energy utilization, metabolism, and cellular respiration.

Energy

The ability to promote change or do work.

Kinetic Energy

Energy associated with movement.

Potential Energy

Energy due to structure or location.

Chemical Potential Energy

Energy stored in the bonds between atoms.

First Law of Thermodynamics

Energy cannot be created or destroyed, only transformed from one type to another.

Second Law of Thermodynamics

Energy transfer increases entropy (degree of disorder).

Free Energy (G)

The usable energy available to do work in a system.

Exergonic Reaction

A reaction where the products have less free energy than the reactants; free energy is released.

Endergonic Reaction

A reaction where the products have more free energy than the reactants; energy must be added.

ATP Hydrolysis

The process where ATP is broken down to release energy, commonly used to drive endergonic reactions.

Enzymes

Biological catalysts that increase the rates of chemical reactions by lowering the activation energy.

Activation Energy (EA)

The initial input of energy required to start a reaction.

Substrate-Product Complex

A temporary complex formed when an enzyme binds its substrate.

Vmax

The maximum rate of an enzyme-catalyzed reaction.

KM (Michaelis-Menten constant)

The substrate concentration at which the reaction rate is half of Vmax.

Competitive Inhibitor

An inhibitor that binds to the active site of an enzyme, competing with the substrate.

Noncompetitive Inhibitor

An inhibitor that binds to an allosteric site, changing the shape of the enzyme and decreasing activity.

Catabolic Reactions

Chemical reactions that break down larger molecules into smaller ones, typically exergonic.

Anabolic Reactions

Chemical reactions that synthesize larger molecules from smaller ones, typically endergonic.

Redox Reactions

Reactions that involve the transfer of electrons between molecules.

Photosynthesis

The process by which plants, algae, and some bacteria convert light energy, water, and carbon dioxide into glucose and oxygen.

Calvin Cycle

The series of biochemical reactions in photosynthesis that converts carbon dioxide into glucose.

Chemiosmosis

The process of ATP generation driven by the movement of H+ across a membrane.

Anaerobic Respiration

A type of respiration that occurs in the absence of oxygen, using other molecules as final electron acceptors.

Fermentation

A metabolic process that produces ATP without oxygen by substrate-level phosphorylation.