Energy and Metabolism in Biological Systems

These flashcards cover key vocabulary and concepts related to energy, metabolism, catalysis, and thermodynamics as discussed in the lecture.

Catalysis

The process of adding a catalyst to speed up a chemical reaction without being consumed in the process.

Metabolism

The sum of all chemical reactions performed by a cell, encompassing both catabolism and anabolism.

Catabolism

The breakdown of complex molecules into simpler components, releasing energy in the process.

Anabolism

The synthesis of larger molecules from smaller precursor molecules, requiring an input of energy.

Activation Energy

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

Enzymes

Biological catalysts that speed up reactions by lowering the activation energy.

Free Energy (ΔG)

The energy in a system that can be used to do work; reactions favor the formation of products with lower free energy.

Entropy

A measure of disorder or randomness in a system; in biological systems, maintaining order requires energy input.

Photosynthesis

The process by which certain organisms convert light energy into chemical energy stored in glucose, involving the capture of carbon dioxide and water.

Redox Reactions

Chemical reactions involving the transfer of electrons between two species, consisting of oxidation (loss of electrons) and reduction (gain of electrons).

Equilibrium Constant (K)

The ratio of the concentrations of products to reactants at equilibrium, indicating the position of the equilibrium state.

Oxidation State

A measure of the degree of oxidation of an atom in a compound, reflecting its electron attraction.

Thermodynamics

The study of energy transformations and the laws governing them, including the behavior of energy in biological systems.

Photosynthesis

The process by which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll.

Entropy (S)

A concept in thermodynamics referring to the unavailability of a system's energy to do work; an increase in entropy reflects a system's progression towards disorder.

Biological Catalyst

A substance that speeds up a biological reaction, like enzymes, without undergoing a permanent change.

Proton Gradient

A difference in proton concentration across a membrane, used by cells to drive ATP synthesis.