membranedominated

Membranedominated is an adjective used in biology, physics, and materials science to describe systems in which a boundary membrane governs the dominant behavior of the whole system. The emphasis is on the membrane’s properties and dynamics as the primary determinants of transport, stability, shape, signaling, and interactions with the environment, rather than the interior bulk material.

In biology, membranes such as the plasma membrane and the membranes surrounding organelles regulate permeability, ion gradients, receptor signaling, and membrane curvature. Domain formation, endocytosis, exocytosis, and vesicle trafficking are often driven by membrane composition (lipids and proteins) and by mechanical properties like tension and bending rigidity. Conceptually, many cellular processes are described as membrane-dominated because changes in the membrane can alter cellular outcomes more than changes inside the cytoplasm.

In synthetic and materials contexts, membrane-dominated behavior appears in liposomes, polymersomes, and hollow microcapsules where a thin surrounding membrane controls stability, cargo release, selective transport, and mechanical response. Such systems rely on membrane properties—composition, thickness, tension, and bending stiffness—to set performance, even when the interior is relatively inert.

Modeling and measurement typically treat the membrane as a two-dimensional surface with parameters such as tension, bending rigidity, spontaneous curvature, and permeability. Theoretical frameworks often involve Helfrich-like bending energy and boundary conditions, while experiments use micromanipulation, AFM, fluorescence recovery after photobleaching, and permeability assays.

Limitations include context-dependence: the term denotes dominance of the membrane in a given regime, and its applicability depends on system scales and competing bulk effects.