Exam 2

Energy Metabolism

All chemical reactions in an organism.

Enzymes

Biological catalysts that speed up chemical reactions in cells.

Catabolic Pathways

Breakdown processes of larger molecules into smaller units, releasing energy.

Anabolic Pathways

Building processes that synthesize larger molecules from smaller units, requiring energy.

Exergonic Reactions

Spontaneous reactions that release energy, with products having less energy than reactants.

Endergonic Reactions

Non-spontaneous reactions that require energy input, with products having more energy than reactants.

First Law of Thermodynamics

Energy of the universe is constant; it can be transformed but not created or destroyed.

Second Law of Thermodynamics

Energy is lost as heat in reactions, increasing disorder or entropy.

ATP

Adenosine triphosphate, the energy currency of the cell, which powers various biological processes.

Glycolysis

The process of breaking down glucose into pyruvate, occurring in the cytosol.

Citric Acid Cycle (Krebs Cycle)

Completes the breakdown of glucose and produces energy carriers like NADH and FADH2.

Oxidative Phosphorylation

Process where high-energy electrons are used to produce ATP in the electron transport chain.

Fermentation

Anaerobic process to generate energy by converting pyruvate into lactic acid or ethanol.

Redox Reactions

Reactions involving the transfer of electrons; oxidation is loss, reduction is gain.

Photosynthesis

The process by which plants convert light energy into chemical energy, producing glucose.

Calvin Cycle

Process in photosynthesis that uses ATP and NADPH to convert CO₂ into glucose.