NBSS - Cellular Structure of the Nervous System Flashcards
1
Q
What is meant by axons being polarised?
What does a neuron consist of?
A
There is a direction of information flow, due to their structure.
There are multiple dendrite on the cell body (soma), with a single axon that ends in the axon terminal.
2
Q
How is information carried along the axons?
A
It is carried by electrical charge.
The axons are polarised membranes. They have a resting potential of -70 mV. They are covered by voltage-gated sodium channels.
A stimulus causes a rebalancing of the ion gradient in the axon by opening the VGSCs, which causes sodium to rush in. this makes the cell ‘depolarise’, as it is getting more positive.
The signal decays over 1-2 millimetres.
