Nerve Cells & Neurotransmission

Nerve Cells & Neurotrasmission

Nerve Cells & Neurotransmission

The Brain:Made up of millions of nerve cells called neurons

Neuron contains 3 Parts:

Dendrites:Receive message

AxonTransmits messages from the cell body to other dendrites or body tissues (muscles)

Cell Body Directs all activities of the neuron

NeurotransmissionTransfer of a message from the axon of 1 nerve cell to the dendrites of another.Does not have direct contact

Neurotransmission

Communication between nerve cells:Occurs through the release of chemical substances (neurotransmitters) into the space between the axon & dendrite (synapse)

When Neurons communicate:A message (electrical impulse) travels down the axon to the synapseThis triggers the release of neurotransmitters into the synapse

Neurotransmitters (chemical messengers) Diffuse across the synapse Bind to receptors This stimulates (starts) or inhibits (stops) an electrical impulse in the receiving neurons dendrites.

Neurotransmitters

Very specificLike a lock & keyReusable

Myelin:Fatty substanceCovers axonsIncreases rate of conduction (how fast the message travels)120 meters/second verses 2 meters/second