Enzymes HL

Intracellular Enzyme Activity

Refers to enzymatic reactions occurring within the cell, such as glycolysis and the Krebs cycle, facilitated by free-floating ribosomes in the cytoplasm.

Extracellular Enzyme Activity

Enzymatic reactions taking place outside the cell, like chemical digestion in the gut, involving ribosomes attached to the rough endoplasmic reticulum and processing of proteins in the Golgi apparatus for release via exocytosis.

Generation of Heat Energy by Metabolism

Process where mammals, birds, and some animals produce heat through metabolic reactions to maintain a constant body temperature, known as endothermy, due to the inefficiency of energy transfer in metabolic reactions.

Cyclical and Linear Pathways in Metabolism

Describes the interconnected series of chemical reactions in an organism's metabolism, with each reaction catalyzed by specific enzymes, forming chains or cycles like glycolysis, the Krebs cycle, and the Calvin cycle.

Competitive Inhibition

Occurs when an inhibitor binds reversibly to the active site of an enzyme, like statins inhibiting HMG-CoA reductase to reduce cholesterol production, while non-competitive inhibitors bind to allosteric sites causing a change in the active site's shape.

Regulation of Metabolic Pathways by Feedback Inhibition

Involves the control of metabolic pathways through end-product inhibition, like the regulation between threonine and isoleucine in a feedback mechanism.

Mechanism-Based Inhibition

Refers to competitive inhibitors that irreversibly bind to the active site of an enzyme, exemplified by penicillin binding to transpeptidases, preventing the construction of peptidoglycan cell walls in bacteria, leading to cell lysis and death.