Biological Neuron

• 
• (from)
• composed of 
  • cell body
  • Dendrites: many branching extensions
  • Axon: very long extension that splits off at its tip into many branches called synaptic terminals
• composed in a network (e.g. brain) by synaptic terminals of one neuron connected to Dendrites of other neurons
• electrical impulses (signals) are sent from other neurons via these synapses
• if a neuron receives a sufficient number of signal from other neurons within a few milliseconds, it is exited and fires its own signals (activation)
• connectivity in a biological neural system is huge, human brain:
  • number of neurons: $\approx 10^{11}$
  • number of connections per neuron: $\approx 10^4$
• networks are organized into hierarchical structures
• Irreplacable
• Requires constant supply of Glucose