Related topics: cells · cell membrane

Mitochondria work much like Tesla battery packs, study finds

For years, scientists assumed that mitochondria—the energy-generating centers of living cells—worked much like household batteries, generating energy from a chemical reaction inside a single chamber or cell. Now, UCLA ...

Insect or virus? How plants know

Most plants have plenty of enemies, from insects and other grazing creatures to various diseases, droughts and many other stressors.

The perfect atomic-scale sieve

Graphene is perfectly selective to protons and blocks even smallest ions like chlorine, University of Manchester research shows. This result will be important for the development of graphene-based membranes for applications ...

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A membrane is a layer of material which serves as a selective barrier between two phases and remains impermeable to specific particles, molecules, or substances when exposed to the action of a driving force. Some components are allowed passage by the membrane into a permeate stream, whereas others are retained by it and accumulate in the retentate stream.

Membranes can be of various thickness, with homogeneous or heterogeneous structure. Membrane can also be classified according to their pore diameter. According to IUPAC, there are three different types of pore size classifications: microporous (dp < 2nm), mesoporous (2nm < dp < 50nm) and macroporous (dp > 50nm). Membranes can be neutral or charged, and particles transport can be active or passive. The latter can be facilitated by pressure, concentration, chemical or electrical gradients of the membrane process. Membranes can be generally classified into three groups: inorganic, polymeric or biological membranes. These three types of membranes differ significantly in their structure and functionality.

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