Action potential potential, such as plant cells, muscle cells, and the specialized cells of the heart (in which occurs the cardiac action potential). However, the main excitable cell is the neuron, which also has the simplest mechanism for the action potential. Neurons are electrically excitable cells composed, in general, of one or more dendrites, a single soma, a single axon and one or more axon terminals. Dendrites are cellular projections whose primary function is to receive synaptic signals. Their protrusions, known as dendritic spines, are designed to capture the neurotransmitters released by the presynaptic neuron. They have a high concentration of ligand-gated
Signals, Crane and Subway, Charters Towers railway station the signal box, although electrical or hydraulic operation could be used for more distant signals. At night, lights were necessary, and kerosene lamps with movable coloured spectacles displayed different colours, including green (proceed), yellow (prepare to find next signal red), and red (stop). Later, electrical coloured lights were used. Smaller points indicator signals, which confirmed whether or not points had been switched, could be used for shunting within a railway yard, and the most common form was the rotating disk signal. These could also contain a kerosene lamp for night operation. To coordinate signals so that is impossible to give