UNIT 2- Vocab

  • Anabolism – Building up molecules (requires energy).

  • Catabolism – Breaking down molecules (releases energy).

  • Enzyme-substrate complex – When an enzyme and a substrate are attached.

  • Activation energy (EA) – Energy needed to start a reaction.

  • Exergonic reaction – Reaction that releases energy.

  • Endergonic reaction – Reaction that requires energy.

  • Gibbs Free Energy (G) – Usable energy in a system.

  • Entropy – Measure of disorder or randomness.

  • Thermodynamics (First and Second Laws) – Rules about energy transfer and transformation.

  • ATP (Adenosine Triphosphate) – Main energy currency in cells.

  • NAD+/NADH – Molecules that carry electrons for energy reactions.

  • NADP+/NADPH – Similar to NAD+/NADH but used in photosynthesis.

  • Active Transport – Movement of molecules against a gradient (requires energy).

  • Facilitated Diffusion – Movement of molecules through a protein channel without energy.

  • Symport – Two substances move in the same direction across a membrane.

  • Antiport – Two substances move in opposite directions across a membrane.

  • Uniport – A single substance moves across a membrane.

  • Aquaporins – Channels that allow water to pass through the cell membrane.

  • Osmosis – Movement of water across a membrane.

  • Hypertonic – Solution with higher solute concentration.

  • Hypotonic – Solution with lower solute concentration.

  • Isotonic – Solution with equal solute concentration.

  • Osmotic Pressure – Pressure caused by water moving across a membrane.

  • Cholesterol in Membranes – Molecules that keep cell membranes flexible.

  • Fluid Mosaic Model – Description of the cell membrane's flexible structure.

  • Phospholipid Bilayer – Double layer of lipids that make up cell membranes.

  • Integral Proteins – Proteins embedded in the cell membrane.

  • Peripheral Proteins – Proteins attached to the surface of the cell membrane.

  • Membrane Permeability – Ability of substances to pass through the membrane.

  • Selective Permeability – Only certain substances can pass through the membrane.

  • Sodium-Potassium Pump – Protein that pumps sodium out and potassium into the cell.

  • Chemiosmosis – Process of making ATP using a proton gradient.

  • Non-cyclic Photophosphorylation – Process that uses light to make ATP and NADPH.

  • Calvin Cycle – Process in plants that uses carbon dioxide to make glucose.

  • Rubisco – Enzyme that helps capture carbon dioxide in the Calvin cycle.

  • Carbon Fixation – Attaching carbon dioxide to make a sugar.

  • Light-Dependent Reactions – First stage of photosynthesis, uses light to make energy.

  • Photosystem II – First step in photosynthesis, captures light energy.

  • Photosystem I – Second step in photosynthesis, captures more light energy.

  • Electron Transport Chain (ETC) – Series of proteins that pass electrons to create energy.

  • Chlorophyll – Green pigment in plants that captures light energy.

  • Chloroplast – Organelle in plants where photosynthesis happens.

  • Stroma – Liquid inside chloroplasts where the Calvin cycle happens.

  • Thylakoid Membrane – Membranes inside chloroplasts where light reactions occur.

  • Granum – Stacks of thylakoid membranes in the chloroplast.

  • Microtubules – Part of the cell's skeleton that helps with movement and structure.

  • Microfilaments – Thin fibers in the cell that help with movement.

  • Intermediate Filaments – Fibers in the cell that provide support and strength.

  • Actin – Protein that makes up microfilaments.

  • Myosin – Protein that interacts with actin for muscle movement.

  • Cytoskeleton – Network of proteins that gives the cell its shape.

  • Cilia – Small hair-like structures on cells for movement.

  • Flagella – Long tail-like structures that help cells move.

  • Kinesin – Protein that helps move things inside the cell.

  • Dynein – Protein that helps cilia and flagella move.

  • Fibronectin – Protein that helps cells stick to the extracellular matrix.

  • Extracellular Matrix (ECM) – Network outside cells that provides structure and support.

  • Basal Body – Structure that anchors cilia and flagella to the cell.

  • Mitochondria – Organelle that produces energy for the cell.

  • Coenzyme – Molecule that helps enzymes work.

  • Cofactor – Non-protein helper needed for enzyme activity.

  • Allosteric Inhibition – When a molecule binds to an enzyme and reduces its activity.

  • Feedback Inhibition – Process where the end product of a reaction stops the reaction from happening again.

  • Competitive Inhibition – When a molecule competes with the substrate for the active site of an enzyme.

  • Non-competitive Inhibition – When a molecule binds elsewhere on an enzyme and changes its shape.

  • Denaturation – When a protein loses its shape and function due to heat or pH changes.

  • Substrate – Molecule that an enzyme acts on.

  • Transition State – The point in a reaction where old bonds break and new bonds form.

  • Induced Fit Model – Model describing how enzymes change shape to fit their substrate.

  • Optimal Temperature – Temperature where an enzyme works best.

  • Optimal pH – pH level where an enzyme works best.

  • Enzyme Saturation – Point where all enzyme active sites are filled with substrate.

  • Substrate Concentration – Amount of substrate available for the enzyme to act on.

  • Rate of Reaction – How fast a reaction occurs.

  • pH Scale – Scale that measures how acidic or basic something is.

  • Kinetic Energy – Energy of movement.

  • Potential Energy – Stored energy.

  • Diffusion – Movement of molecules from high concentration to low concentration.

  • Passive Transport – Movement of molecules across a membrane without energy.

  • Light-Independent Reactions – Second stage of photosynthesis, doesn't need light (Calvin cycle).

  • Quaternary Protein Structure – Structure formed by multiple protein subunits.

  • Activation Site – Part of an enzyme where the substrate binds.

  • Energy Coupling – Using energy from one reaction to power another.

  • Energy Diagrams – Graphs showing the energy changes during a reaction.

  • Metabolic Pathways – Series of chemical reactions in a cell.