Biological Communication Systems
Describe the different parts of the nervous system; the central nervous system and the periphery system.
Your description should go on to include the structure of the sensory, connector and motor neurones. Then
illustrate the role these neurones play in the reflex action and compare this with a voluntary action.
Give an illustrated explanation of the role of the autonomic nervous system.
The graph below shows the changes in potential difference across the membrane of a neurone before and
after stimulation.
i) Identify the point on the graph that represents resting potential and describe how the potential
difference at this point is maintained in the neurone.
ii) Describe how an action potential is generated in a neurone and how it is then transmitted along the
neurone as a nerve impulse.
Explain the role of chemical transmitters in enabling the nerve impulse to cross a synapse to the next neurone.
Explain the effects of one of the following drugs on the transmission of nerve impulses: caffeine, nicotine,
amphetamines or cocaine.
