There is a tiny space at the junction between 2 neurones.

  • junction between the 2 neurones is called a synapse. Nerve impulses cannot directly cross from 1 neurone to the next due to the tiny space between them. Nerve impulses are transmitted across a synapse by chemicals released by the neurones.


Important

  • Impulses are transmitted from axon of one neurone to dendron of another neurone across a minute space → called synapse

Alternative?

  • Electrical impulses → cannot jump across this gap
  • Production of chemical substance is stimulated (WHERE)
  • Chemical substance (neurotransmitter) → flows across synapse and stimulates next nerve→ to start electrical impulse

Advantages of Having Synapses rather than one long continuous nerve fibre
  • synapse → makes it possible for 1 nerve → to stimulate impulses in several other nerves at same time
  • Presence of neurotransmitters → can allow us → to administer certain drugs → to prevent transmission of chemical signals → thus blocking nerve impulses