Search results
Results From The WOW.Com Content Network
The incoming action potential activates voltage-gated calcium channels, leading to an influx of calcium ions into the axon terminal. The SNARE complex reacts to these calcium ions. It forces the vesicle's membrane to fuse with the presynaptic membrane , releasing their content into the synaptic cleft within 180 μs of calcium entry.
An action potential is an "all-or-none" event; neurons whose membranes have not reached threshold will not fire, while those that do must fire. Once the action potential is initiated (traditionally at the axon hillock ), it will propagate along the axon, leading to release of neurotransmitters at the synaptic bouton to pass along information to ...
Once this initial action potential is initiated, principally at the axon hillock, it propagates down the length of the axon. Under normal conditions, the action potential would attenuate very quickly due to the porous nature of the cell membrane. To ensure faster and more efficient propagation of action potentials, the axon is myelinated ...
An axon (from Greek ἄξων áxōn, axis) or nerve fiber (or nerve fibre: see spelling differences) is a long, slender projection of a nerve cell, or neuron, in vertebrates, that typically conducts electrical impulses known as action potentials away from the nerve cell body.
The action potential in a normal skeletal muscle cell is similar to the action potential in neurons. [61] Action potentials result from the depolarization of the cell membrane (the sarcolemma), which opens voltage-sensitive sodium channels; these become inactivated and the membrane is repolarized through the outward current of potassium ions ...
This glossary of biology terms is a list of definitions of fundamental terms and concepts used in biology, the study of life and of living organisms.It is intended as introductory material for novices; for more specific and technical definitions from sub-disciplines and related fields, see Glossary of cell biology, Glossary of genetics, Glossary of evolutionary biology, Glossary of ecology ...
The action potential, which typically starts at the axon hillock, propagates down the length of the axon to the axon terminals where it triggers the release of neurotransmitters, but also backwards into the dendrite (retrograde propagation), providing an important signal for spike-timing-dependent plasticity (STDP).
The signal is a short electrical pulse called action potential or 'spike'. Fig 2. Time course of neuronal action potential ("spike"). Note that the amplitude and the exact shape of the action potential can vary according to the exact experimental technique used for acquiring the signal.