BIOL362-weeks 1-2

Metabolism

The set of life-sustaining chemical reactions in organisms that enable them to maintain life and energy.

Second Law of Thermodynamics

Energy transformations are not 100% efficient; energy is lost as heat, causing entropy to increase.

Aerobic Metabolism

A metabolic process that requires oxygen to generate ATP from glucose and other substrates.

Anaerobic Metabolism

A metabolic process that occurs without oxygen, typically producing less ATP quickly from glucose.

Krebs Cycle

Also known as the Citric Acid Cycle, it is a series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetyl-CoA.

ATP (Adenosine Triphosphate)

The primary energy carrier in cells, providing energy for various cellular processes.

Respiratory Quotient (RQ)

The ratio of carbon dioxide produced to oxygen consumed during metabolism.

Calorimetry

A technique used to measure the amount of heat produced by an organism to determine metabolic rate.

Direct Calorimetry

A measure of heat produced by an organism to quantify energy expenditure.

Indirect Calorimetry

A method for estimating energy expenditure by measuring the amount of oxygen consumed or carbon dioxide produced.

Proton Motive Force (PMF)

The force generated by a transmembrane gradient of protons, used to drive ATP synthesis.

Glycolysis

The metabolic pathway that breaks down glucose into pyruvate, generating ATP and NADH in the process.

Entropy

The measure of disorder or randomness in a system, which tends to increase in isolated systems over time.

Thermoneutral Zone (TNZ)

The range of ambient temperatures within which an animal can maintain its body temperature without expending energy on heating or cooling.

Field Metabolic Rate (FMR)

The rate of energy expenditure by an animal in its natural environment.

Doubly-Labelled Water (DLW)

A method for measuring metabolic rate by tracking the elimination of isotopes of hydrogen and oxygen from the body.

Specific Dynamic Effect

The increase in metabolic rate following the digestion and assimilation of food.

Lactate

A byproduct of anaerobic metabolism, often accumulated during high-intensity activity.

Homeostasis

The ability of an organism to maintain a stable internal environment despite external changes.

Electron Transport Chain (ETC)

A series of protein complexes and other molecules that transfer electrons through redox reactions to generate ATP.

Mitochondria

The powerhouse of the cell; organelles that generate ATP through oxidative phosphorylation.

Heterotrophs

Organisms that obtain their energy by consuming other organisms or organic matter.

Anabolic Processes

Metabolic pathways that construct molecules from smaller units, requiring energy.

Catabolic Processes

Metabolic pathways that break down molecules into smaller units, releasing energy.

Resting Metabolic Rate (RMR)

The rate of energy expenditure when an organism is at rest, but awake and not actively digesting food.

Basal Metabolic Rate (BMR)

The rate of energy expenditure at rest in a post-absorptive state, typically measured at a neutral temperature in a fasting individual.

Allostasis

The process through which the body responds to stressors in order to regain homeostasis.

Thermoregulation

The process by which organisms maintain their body temperature within certain boundaries.