Energy and Cellular Processes (Ch. 4-6 Study Guide)

Vocabulary flashcards generated from Chapters 4-6 Study Guide covering enzyme function, cellular transport, photosynthesis, and cellular respiration.

Alcohol Dehydrogenase Reaction

A chemical reaction where ethanol is converted into acetaldehyde by alcohol dehydrogenase (ADH).

Acetaldehyde

A toxic substance produced by the breakdown of ethanol that causes hangover symptoms.

Activation Energy

The energy needed to start a reaction, representing the energy hill that reactants must climb.

Enzyme

A biomolecule (mostly protein) that speeds up chemical reactions by lowering activation energy.

Metabolism

All the chemical reactions that happen within a cell.

Adenosine Triphosphate (ATP)

A molecule consisting of adenine, ribose, and three phosphate groups that stores and transfers energy to power cell activities.

Active Site

The region of an enzyme that recognizes and binds its substrate based on shape, size, polarity, and charge.

Phosphorylation

The process in which an enzyme or molecule receives a high-energy phosphate group (such as from ATP), activating or modifying it.

Product Inhibition

A decrease in reaction rate or complete shutdown caused by a buildup of reaction products inhibiting the enzyme.

Equilibrium (Concentration Gradient)

The state where solute concentration is equal on both sides, causing the concentration gradient to disappear.

Simple Diffusion

Passive transport of small, nonpolar molecules across a membrane following their concentration gradient from high to low concentration without using energy.

Osmosis Direction

The movement of water from a hypotonic solution to a hypertonic solution until both sides become isotonic.

Exocytosis

A process where a vesicle fuses with the cell membrane to release its contents outside the cell.

Phagocytosis

A form of bulk transport used by a cell to engulf large particles, such as bacteria.

Fossil Fuels

Energy sources such as coal, petroleum, and natural gas derived from the buried organic remains of ancient prehistoric organisms.

Mid-1800s Carbon Dioxide Increase

The historical period in the mid-1800s when atmospheric carbon dioxide levels began rising rapidly due to heavy human fossil fuel consumption.

Chloroplast

The cell organelle where photosynthesis occurs, using light energy to produce sugars from carbon dioxide and water.

Light-Dependent Reactions

Photosynthetic reactions in the thylakoid membrane that use light energy to produce ATP and NADPH.

Pigment Reflection

The principle that a pigment's visible color is determined by the color of light it reflects rather than absorbs.

Accessory Pigments

Pigments that become visible when chlorophyll breaks down, such as during autumn.

Photosystems

Structures in the thylakoid membrane to which chlorophyll transmits absorbed light energy.

Calvin-Benson Cycle

The light-independent reactions occurring in the stroma that use $CO_2$, ATP, and NADPH to synthesize sugars.

Free Radicals (Oxygen)

Reactive molecules formed when oxygen combines with escaped electrons from the electron transfer chain.

Glycolysis

The first step of aerobic cellular respiration occurring in the cytoplasm, yielding a net total of $2\text{ ATP}$.

Inner Mitochondrial Membrane

The folded inner membrane of the mitochondrion that contains proteins for ATP production and the electron transport chain.

Acetyl-CoA

The reactant that enters the Krebs cycle to be broken down to harness high-energy electrons and ATP.

ATP Synthase Activation (Cellular Respiration)

The enzyme process powered by the facilitated diffusion flow of $H^+$ ions moving from the intermembrane space into the matrix.

Fermentation Location

The cytoplasm of the cell, where fermentation takes place.