Slides in this set
Neurons are cells which can transmit electrical impulses to the brain. They do not
touch each other so there are gaps between them which are called synapses.
Electrical impulses are transmitted across synapses by chemicals as the electrical
impulse cannot just jump across the gap. This is how synapses transmit nerve
· Firstly the nerve impulse arrives at the synapse
· A chemical is released from the sensory neuron and diffuses across the synapse
to help the impulse get across the gap. The molecule fits into the receptor
molecules on the motor neuron's membrane
· The nerve impulse is then transmitted along by the motor neuron and the
chemical is absorbed back into the sensory neuron where it can be used to
Synapses don't slow down nerve
impulses that much because they are
only tiny gaps.…read more
Serotonin, Prozac and Ecstasy
Serotonin is a chemical which is released at certain synapses in the brain. It gives
feelings of pleasure.
Prozac is an antidepressant which causes serotonin to build up at the synapses of
the brain. This makes the patient have feelings of pleasure (feel happy). It works
by blocking the reuptake of serotonin.
Ecstasy is a recreational drug which works in a similar way to Prozac and is sad to
give feelings of pleasure. However long-term use of ecstasy may destroy the
synapses which release serotonin which could lead to depression and anxiety.
Aswell as this it also slows down the production of ADH and therefore can affect
the temperature of the body.…read more