How do neurons use neurotransmitters to communicate with each other and with the body?
- The brain is made up two types of cells, neurons and glial cells.
Neurons have dendrites
, which receive input, a soma
or cell body, and axons
that carry the neural message to other cells.
Glial cells separate, support and insulate the neurons from each other and make up 90 percent of the brain.
insulates and protects the axons of the neurons that travel in the body. These axons bundle together in cables called nerves
. Myelin also speeds up the neural message.
Neurons in the peripheral nervous system are also coated with neurilamma
, which allows the nerves to repair themselves.
A neuron contains charged particles called ions
. When at rest, the neruon is negatively charged on the inside and positively charged on the outside. When stimulated, this reverses the charge by allowing positive sodium ions to enter the cell. This is the action potential
Neurons fire in an all-or-nothing
manner. It is the speed and number of neurons firing that tell researchers the strength of the stimulus.
in the end of the axon terminal release neurotransmitter chemicals into the synapse
, or gap, between one cell and the next. The neurotransmitter molecules fit into receptor sites
on the next cell, stimulating or inhibiting that cell's ifring. Nuerotransmitters may be either excitatory
The first known neurostramitter was acetycholine
. It simulates muscles and helps in memory formation, Curare
is a poison that blocks its effect.
is the major inhibitory neurotransmitter. High amounts of GABA are released when drinking alchohol.
is associated with sleep, mood and appetite.
is assoicated with Parkinsons' disease and schizophrenia.
are neural regulators that control our pain response.
Most neurotransmitters are taken back into the synpatic veiscles in a process called reuptake
Aethycholine is cleared out of the synapse by enzymes that break up the molecules.