Neuronal Communication Flashcards
What are neurones?
Specialised cells that conduct nerve impulses
What do sensory neurones do?
Transmit action potentials from sensory receptors to other neurones
What do relay neurones do?
Transmit action potentials from sensory neurones to motor neurones
What do motor neurones do?
Transmit action potentials from the Central Nervous System or relay neurones to muscle or glands
What do reflexes bypass?
The central nervous system
Where is the cell body located on a sensory neurone?
in the middle of the dendron and axon
Where is the cell body located on a motor neurone?
At the dendron end
What direction does an impulse travel along a neurone?
From the dendron to the axon
What does myelin act as?
An electrical insulator, speeding up the conduction of action potentials along an axon
Where is myelinated?
Along the long axons within the nervous system (white matter)
Where is non-myelinated?
In neuronal body cells and dendrites (grey matter)
How do action potentials travel when myelinated?
Action potentials jump along axons at nodes of Ranvier by saltatory conduction
Does myelination make the axon wider or narrower?
Wider
Does myelination make transmission faster or slower?
Faster
How do action potentials travel along non-myelinated neurones?
Occur throughout the whole length of the axon
