Study Guide Bio Unit 3

Amino Acid

The monomer that makes up an enzyme.

Enzyme

A protein that catalyzes chemical reactions by lowering the activation energy.

Active Site

The specific region of an enzyme where the substrate binds.

Enzyme-Substrate Complex

The temporary complex formed when a substrate binds to an enzyme.

Induced Fit

The slight change in the enzyme's shape to accommodate a substrate after binding.

Catalyst

A substance that speeds up a chemical reaction without being consumed.

Activation Energy

The minimum energy required for a chemical reaction to occur.

Gibbs Free Energy

A measure of the energy available to do work in a reaction; enzymes do not affect its overall change.

Denaturation

The process by which a protein loses its natural shape and function, typically due to environmental conditions.

pH

A measure of the acidity or basicity of a solution that can affect enzyme activity.

Competitive Inhibitor

A molecule that binds to the active site of an enzyme, preventing substrate binding.

Noncompetitive Inhibitor

A molecule that binds to a site other than the active site, altering enzyme function.

Fermentation

A metabolic process that produces energy anaerobically, converting carbohydrates into acids, gases, or alcohol.

Glycolysis

The metabolic pathway that converts glucose into pyruvate, producing ATP and NADH.

Krebs Cycle (Citric Acid Cycle)

A series of reactions through which all aerobic organisms generate energy from acetyl-CoA.

Electron Transport Chain

A series of protein complexes that transfer electrons and create a proton gradient for ATP synthesis.

ATP (Adenosine Triphosphate)

The energy currency of the cell, used to power biological processes.

Exergonic Reaction

A reaction that releases energy, resulting in products with lower energy than the reactants.

Endergonic Reaction

A reaction that absorbs energy, resulting in products with higher energy than the reactants.

Energy Coupling

The use of energy released from exergonic reactions to drive endergonic reactions.

Entropy

The measure of disorder within a system; increases in isolated systems over time.

Photosynthesis

The process by which organisms convert light energy into chemical energy stored in glucose.

Calvin Cycle

The set of reactions in photosynthesis that convert carbon dioxide to sugars using ATP and NADPH.

Chlorophyll

A green pigment in plants that captures light energy for photosynthesis.

Proton Gradient

A difference in proton concentration across a membrane that enables ATP synthesis.

Oxidative Phosphorylation

The metabolic pathway that generates ATP from ADP using the energy derived from electron transport.

Photophosphorylation

The process of generating ATP from ADP and inorganic phosphate using light energy during photosynthesis.

Cellular Respiration

The process of producing ATP by breaking down glucose in the presence of oxygen.

NADH and FADH2

Reduced cofactors that carry electrons to the electron transport chain.

Chemical Reaction

A process that leads to the transformation of one set of chemical substances into another.

Hydrolysis of ATP

The process of breaking down ATP into ADP and inorganic phosphate, yielding energy.

Thermodynamics

The study of energy transformations, including laws governing energy conservation and entropy.

Metabolic Pathway

A series of connected chemical reactions within a cell that build or break down molecules.

Biological Catalyst

A term that refers to enzymes which accelerate biochemical reactions in living organisms.

NAD+

A coenzyme that acts as an electron carrier in cellular respiration.

Mitochondria

Organelles that serve as the site for cellular respiration and ATP production.

Cytoplasm

The jelly-like fluid inside a cell where glycolysis occurs.

Acetyl-CoA

A molecule derived from pyruvate that enters the Krebs cycle for further energy extraction.

Cellular Environment

The internal conditions of a cell that can influence enzyme activities and reaction rates.

Enzymatic Activity

The ability of an enzyme to catalyze a chemical reaction efficiently.

Homeostasis

The maintenance of stable internal conditions in an organism.

Biochemical Reactions

Chemical processes that occur in living organisms to maintain life.

Prokaryotic Organisms

Single-celled organisms that lack membrane-bound organelles, such as bacteria.

Enzyme-Substrate Interaction

For an enzyme-mediated chemical reaction to occur, the shape and charge of the substrate must be compatible with the active site of the enzyme.