Thermodynamics and Bioenergetics

Flashcards on Thermodynamics and Bioenergetics

Energy

Capacity to perform work.

Kinetic Energy

Energy in the process of doing work or energy of motion (Heat, Light).

Potential Energy

Energy content of a matter, because of its arrangement or position.

Thermodynamics

The study of energy transformations that occur in a collection of matter.

Bioenergetics

The thermodynamics in living organisms.

Living Systems

Living systems = Environments + Organisms.

Conduction

Energy is transferred by direct contact.

Convection

Energy is transferred by the mass motion of molecules.

Radiation

Energy is transferred by electromagnetic radiation.

First Law of Thermodynamics

Energy cannot be created or destroyed, but only converted to other forms; the amount of energy in the universe is constant.

Second Law of Thermodynamics

All energy transformations are inefficient because every reaction results in an increase in entropy and the loss of usable energy (free energy) as heat.

Enthalpy (H)

The total heat of a system.

Free Energy (G)

The amount of usable energy in a system that can be used to perform work.

Entropy (S)

The amount of disorder in a system; in most cases, it is heat.

Gibbs Free Energy (G)

Expresses the amount of energy capable of doing work during a reaction at constant temperature and pressure.

Enthalpy (H)

The heat content of the reacting system; reflects the number and kinds of chemical bounds in the reactants and products.

Exothermic Reaction

A chemical reaction that releases heat; ΔH has a negative value

Endothermic Reaction

Reacting systems that take up heat from their surroundings and have positive values of ΔH

Cellular Metabolism

The sum total of the chemical activities of all cells.

Anabolic Pathways (Endergonic reactions)

Pathways that consume energy to build complicated molecules from simpler compounds.

Catabolic Pathways (Exergonic reactions)

Pathways that release energy by breaking down complex molecules into simpler compounds.

Oxidation

Gain of Oxygen, Loss of Hydrogen, Loss of electrons.

Reduction

Gain of Hydrogen, Gain of electron, Loss of Oxygen.

ATP Components

adenine, ribose, phosphate group.

Phosphorylation

Process of weakening and breaking last PO4 bond releasing energy & free PO4, occurs continually in cells with Enzyme ATP-ase

Coupled Reaction - ATP

The exergonic hydrolysis of ATP is coupled with the endergonic dehydration process by transferring a phosphate group to another molecule

Hydrolysis of ATP Description

Hydrolysis (add water) ATP + H2O → ADP + P.

Dehydration of ATP Description

Dehydration (Remove H2O) ADP + P → ATP + H2O.