History of Electrical Excitation in Evolved Cells

Excitability is regarded as a main feature of living systems. Electrical excitation was earlier thought to be expressed only in nervous and muscle tissue. Later it turned out that similar phenomena are observed also in plants. Even more, reassembly experiments showed that algal protoplasmic drops display membrane potential and its changes resemble action potentials.Excitability has been described in epithelia, plant cells, algae, protozoa, and ova.  

In the history of development of living systems, the membrane was the primary constituent element of the cell. What are the physical and chemical premises of an organization of the membrane and cell  

The only up-to-date suitable experimental model to help answer this question is the proteinoid cell assembled from thermal proteins, or proteinoids. To date, no other experimental protein-related model of the first cell has been shown to have comparable properties. 

In 1973 the first finding of excitability in a proteinoid cell was reported. These data were further expanded.Transmission electron microscope evidence of a double membrane in these cells,selective permeability, and osmotic properties as well as bilayer membranes made of proteinoidsprovide an experimental background to understanding the origin of excitability. 

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