Intro To Nervous System Flashcards
In a neurone, where do action potentials start?
dendirtes
Why do neurones are large with a large nucleus and nucleolus?
Lots of protein synthesis
Very metabolic
What is the name for the cell body of a neurone?
Soma or perikaryon
What are the 3 types of neurones?
Multipolar, bipolar, unipolar
Neurones can be unipolar, bipolar or multipolar. What do these terms mean?
Unipolar - one dendrite to one axon
Bipolar - 2 dendrites to one axon
Multipolar - many dendrites to one axon
What is the basic reflex ac
Stimulus Receptor Sensory neurone Relay neurone (CNS) Motor neurone Effector Response
What do Schwann cells produce?
Myelinated sheath around axons
In which nervous system are Schwann cells found?
Peripheral
What is saltatory conduction
Depolarisation at nodes of Ranvier
Fast jumping impulse
What factors increase conduction
Myelination
Thick axon diameter
Higher temperature
What provides the myelin sheath for the CNS? How many supply each axon?
Oligodendrocytes
One oligodendrocyte supports several axons
What does afferent and efferent mean in terms of innervation?
Afferent is towards the cel
Efferent is away from the cell
In the sympathetic nervous system, what are the relative lengths of the preganglionic and postganglionic fibres?
Preganglionic short
Postganglionic long
In the parasympathetic nervous system, what are the relative lengths of the pre and post ganglionic axons?
Long preganglionic
Short postganglionic
What is a ganglion?
Nerve cell cluster in PNS
