Peak temperatures in December in Hawaii can reach levels of up to 26Â°C on average. However, in 1988, Hawaii recorded its highest ever temperature in December, where the thermometer reached an incredible 31Â°C. There is no chance of a white Christmas on the beaches in Hawaii, unless you include the whiteness of the sand.
2) Synaptic Cleft: This is the narrow gap between the axon terminal of the presynaptic neuron, and the post-synaptic membrane of another excitable cell. It is filled with extracellular fluid. 3) Postsynaptic membrane: The membrane across the synaptic cleft is called the postsynaptic membrane.) A nerve impulse reaches the axon terminal of a presynaptic neuron; the membrane is depolarised by an action potential. 2) Depolarisation of the axon terminal during the action potential causes voltage sensitive calcium ion channels to open in the terminal knob.
The junction between the axon terminals of a neuron and the receiving cell is called a synapse. (Synapses at muscle fibers are also called neuromuscular junctions or myoneural junctions 1  .). Action potentials travel down the axon of the neuron to its end(s), the axon terminal(s).