Metabolism and Bioenergetics Vocabulary

Vocabulary flashcards based on lecture notes about metabolism and bioenergetics.

Metabolism

All chemical reactions in an organism.

Enzymes

Selectively accelerate each step in metabolic pathways.

Catabolism

The processes of breaking down large molecules into simpler compounds to release energy; main pathway is cellular respiration.

Anabolism

Reactions that use energy to obtain complex molecules from simpler molecules.

Bioenergetics

Examines how living organisms utilize their energy sources.

Energy

The capacity to do work; the ability to move matter against opposing forces or to rearrange a group of substances.

Kinetic Energy

Energy possessed by everything in motion.

Potential Energy

Energy that matter possesses due to its position or structure.

Thermodynamics

The study of energy transformations in matter.

System (Thermodynamics)

The substance being studied in thermodynamics.

Surroundings (Thermodynamics)

Objects outside of the system in thermodynamics.

Closed System

Systems isolated from their surroundings.

Open System

Systems that continuously exchange energy with their surroundings.

Zeroth Law of Thermodynamics

If objects A and B are in thermal equilibrium with each other and with object C, then C is also in thermal equilibrium with A and B.

First Law of Thermodynamics

The energy in the universe is constant; energy can be transferred or converted but not created or destroyed. Also known as the principle of conservation of energy.

Second Law of Thermodynamics

Every energy transfer or transformation increases the entropy (disorder) in the universe.

Entropy

A measure of disorder or randomness in a system.

Third Law of Thermodynamics

As the temperature approaches absolute zero (0 Kelvin), the entropy of all particles will approach a constant and become nearly equal.

Spontaneous events

Events that occur without the need for external energy.

Non-spontaneous events

Events that require the application of energy from an external source.

Free energy

The energy within a system that has the ability to do work.

ΔG

Symbol for the amount of free energy change.

Exergonic reactions

Reactions that release free energy to the surroundings; spontaneous reactions with ΔG is negative (ΔG < 0).

Endergonic reactions

Reactions that absorb energy from the surroundings during their occurrence; non-spontaneous reactions with ΔG is positive (ΔG > 0).

Metabolic imbalance

A state where there is a continuous flow of substances into or out of the cell prevents metabolic pathways from reaching equilibrium allowing the cell to continue performing work throughout its life.