Kompartimente

Kompartimente (compartments) are discrete structural and functional units within a larger system, separated by boundaries that localize processes and create distinct environments. In biology, many compartments are membrane-bound organelles of eukaryotic cells, including the nucleus, mitochondria, chloroplasts, endoplasmic reticulum, Golgi apparatus, lysosomes, peroxisomes, and various vacuoles. Non-membrane-bound compartments also exist, such as the nucleolus or ribosome clusters. Boundaries are typically phospholipid membranes that regulate the passage of ions, molecules, and macromolecules through selective transport proteins.

The main functions of compartments are to specialize biochemical reactions, maintain suitable conditions for those reactions (such as pH and ion balance), protect sensitive processes from competing activities, and enable efficient regulation and coordination of metabolism. They also enable the segregation of harmful byproducts and allow sequential reaction steps to occur in the correct order.

Transport between compartments occurs through channels, pumps, vesicular trafficking, and membrane fusion events. In plant and animal cells, compartmentalization supports energy production, storage, protein processing, and signaling. Evolutionarily, mitochondria and chloroplasts are derived from endosymbiotic ancestors, retaining some of their own DNA and double membranes.

In physiology and pharmacology, the term is extended to describe body-fluid compartments (intracellular and extracellular; the latter including plasma and interstitial fluid) used to model distribution and kinetics of substances. The concept of Kompartimente thus underpins much of cell biology, physiology, and pharmacology.