Enzymes, Energy, and Biological Reactions

Flashcards covering key terminology and concepts from the lecture on enzymes, energy, and biological reactions.

Activation Energy

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

Catalyst

A chemical agent that accelerates the rate of a reaction without being changed by it, most biological catalysts are enzymes.

Enzyme

A type of protein that catalyzes biological reactions by lowering the activation energy.

Substrate

The molecule that an enzyme acts on, which must fit perfectly into the enzyme's active site.

Induced Fit

A model describing how enzymes change shape to better fit the substrate upon binding.

Enzyme-Substrate Specificity

The concept that each enzyme only catalyzes specific substrates or groups of closely related molecules.

Competitive Inhibition

A type of enzyme inhibition where an inhibitor competes with the substrate for the active site.

Noncompetitive Inhibition

A type of enzyme inhibition where an inhibitor binds to an allosteric site, reducing the enzyme's activity.

Potential Energy

The stored energy in an object due to its position or state.

Kinetic Energy

The energy of an object in motion.

First Law of Thermodynamics

The law stating that energy cannot be created or destroyed, only transformed or transferred.

Second Law of Thermodynamics

The law stating that the total disorder of a system always increases, and no energy transformation is 100% efficient.

Endergonic Reaction

A chemical reaction that requires or absorbs energy.

Exergonic Reaction

A chemical reaction that releases energy.

Adenosine Triphosphate (ATP)

A nucleotide that serves as the energy currency of the cell, consisting of ribose, adenine, and three phosphate groups.

Hydrolysis of ATP

A reaction that breaks down ATP into ADP and a phosphate, releasing energy.

Energy Coupling

The process where energy released from exergonic reactions is used to drive endergonic reactions.

Phosphorylation

The addition of a phosphate group to a molecule, often facilitated by ATP.

Renewable Energy Storage

The ability of ATP to be hydrolyzed and resynthesized, making it an efficient energy storage molecule.

Enzymatic Reaction

A reaction that is catalyzed by an enzyme.

Hydrolysis Reaction

A reaction that breaks chemical bonds through the addition of water.

Dehydration Synthesis Reaction

A reaction that forms chemical bonds by removing water.

Allosteric Site

A site on an enzyme where an inhibitor can bind, affecting the enzyme's activity.

Chemical Bonds

The connections between atoms that hold molecules together, broken in exergonic reactions.

Entropy

A measure of disorder in a system, which always increases according to the Second Law of Thermodynamics.

Ribose

A five-carbon sugar that is part of the structure of ATP.

Phosphate Group

A group consisting of phosphorus bonded to four oxygen atoms, key in ATP structure.

Phosphate Molecule (P)

A molecule that is released during the hydrolysis of ATP.

Chemical Energy

Energy stored in the bonds of chemical compounds.

Biological Catalysts

Proteins that speed up biological reactions, primarily enzymes.

Rate of Reaction

The speed at which reactants are converted to products in a chemical reaction.

Organism Control

The ability of an organism to regulate when and where reactions occur.

Three-Dimensional Structure

The specific shape of a protein determined by its amino acid sequence, affecting its function.

Hydrolysis Reaction and Energy Release

The breakdown of ATP that releases a significant amount of energy.

Energy Transfer

The movement of energy from one form or place to another, regulated by thermodynamics.

Metabolism

The totality of chemical reactions within a living organism.

Energy from Food

The energy released from the breakdown of carbohydrates, proteins, and fats used for ATP synthesis.

Cellular Work

The various tasks performed by cells that require energy.

Loading and Unloading of ATP

The process of adding and removing phosphate groups from ATP during energy transfer.

Energy Conversion

The process of changing energy from one form to another.