Metabolism and Energy Production

This set of flashcards covers key terms and definitions related to metabolism and energy production processes, essential for understanding how the body generates and utilizes energy.

ATP (Adenosine Triphosphate)

The immediate source of energy for almost all bodily functions, including muscle contraction.

Phosphocreatine (PCr)

A high-energy phosphate molecule that donates Pi to ADP to form ATP in the ATP-PCr system.

Glycolysis

The breakdown of glucose or glycogen to produce ATP, resulting in pyruvic acid.

Substrate-Level Phosphorylation

The production of ATP without the use of oxygen, primarily occurring in glycolysis and the ATP-PCr system.

Oxidative Phosphorylation

The process by which ATP is produced using oxygen, occurring in the mitochondria via the electron transport chain.

Beta-Oxidation

The process of breaking down fatty acids into acetyl CoA for entry into the Krebs cycle.

Krebs Cycle

A series of chemical reactions in the mitochondria that generate ATP, NADH, and FADH2 from acetyl CoA.

Lactic Acid

A by-product of anaerobic glycolysis, often associated with muscle fatigue.

Rate-Limiting Enzyme

An enzyme that regulates the speed of a metabolic pathway, such as phosphofructokinase (PFK) in glycolysis.

Cori Cycle

The process by which lactate produced in muscles is transported to the liver, converted back to glucose, and returned to the muscles.

Energy Yield From Carbohydrate Oxidation

The complete oxidation of glucose produces 32 ATP; from glycogen, it yields 33 ATP.

Creatine Kinase

An enzyme that catalyzes the conversion of phosphocreatine to ATP and is regulated by ATP and ADP levels.

Anaerobic Metabolism

Energy production that occurs in the absence of oxygen, including the ATP-PCr and glycolytic systems.

Mitochondria

Cell organelles where oxidative phosphorylation occurs, producing the majority of ATP in aerobic metabolism.