The United States Navy has twenty six grades of enlisted sailors and officers, with most sailors enlisting at the entry-level rank of Seaman Recruit (SR, paygrade E-1). The highest rank achievable in the Navy is Fleet Admiral.
Photo by: Sebastian Kaulitzki. The neuron (nerve cell) is the fundamental unit of the nervous system. The basic purpose of a neuron is to receive incoming information and, based upon that information, send a signal to other neurons, muscles, or glands. Neurons are designed to rapidly send signals across physiologically long distances. They do this using electrical signals called nerve impulses or action potentials. When a nerve impulse reaches the end of a neuron, it triggers the release of a chemical, or neurotransmitter. The neurotransmitter travels rapidly across the short gap between cells (the synapse) and acts to signal the adjacent cell.
The presynaptic neuron is the neuron whose axon forms a synapse with the dendrite of another neuron. The presynaptic neuron sends out information. The postsynaptic neuron is the neuron whose dendrite forms a synapse with the axon of the presynaptic neuron. The postsynaptic neuron receives information.ommunication between neurons is the foundation for brain function. Understanding how neurotransmission occurs is crucial to understanding how the brain processes and integrates information. Interruption of neural communication causes changes in cognitive processes and behavior.