Action Potential in an unmyelinated axon

An action potential,depicted as a red band, is propagated in one directional along the axon.During an action potential , the inside of the cell membrane becomes positive with respect to the outside.An action potential generates local current that tends to depolarize the membrane immediately adjacent to the action potential,When depolarization caused by the local currents threshold, a new action potential adjacent to the original one.Action potential propagation occurs in one directional because the recently depolarized area of the membrane is in absolute refractory period and cannot generate an action potential.

Animation on Bacterial sporulation

A bacterium undergoing sporulation will first replicate its DNA ,The replicated DNA as well as a small amount of cytoplasm is segregated at one end of the cell,The plasmid membrane of the bacterium then grows inwards to eventually separate replicated DNA and the surrounding cytoplasm from the rest of the cells. water diffuses from this small segregated portion into the surrounding cell and then new endospore develops a thick protein coat once the formation of the endospore is complete the original cell wall dissolves and parent cell dies. the endospore is released from the dead parent cell