membrane & action potential

what is a neurone?

structural & functional unit of the nervous system

how do neurones communicate?

synapses (gap between neurones)

what do neurones form when connected with each other?

neural circuits

in what direction do electrical signals travel in the neurone?

dendrites > cell body > axon > axon terminals

what is the action potential?

a nerve impulse

acronym for the sodium potassium pump explained? – NOKIA

N - Na+

O – OUT

K - K+

I – IN

A - ATP USED

what does the phospholipid bilayer do?

barrier used to isolate the cell contents from outside of cell.

what do transmembrane proteins control?

the passage of ions in / out of the neuron

what type of permeable is the neuronal membrane?

semi-permeable

inside of the cell Na,K ratio?

inside of cell - High K+, low Na+

outside of the cell Na,K ratio?

outside of cell - Low K+, High Na+

action potential process?

in NA,K,ATPASE

Voltage gated Na+ channels open, leading to an influx of Na+, depolarising the cell. Voltage gated Na+ channels inactivate and voltage gated K+ channels open, leading to an influx of K+ efflux, repolarising the cell and closes the K+ voltage gated channels.

what is a dendrite?

a short branched extension of a nerve cell, which carries impulses.

what does each dendritic spine form?

a single synapse

what do a high number of dendritic spines cause?

high neuronal connectivity

what structural features of dendritic spines allow it to be better at its job?

the spines are dynamic, being able to change shape = role in memory and learning.

what does the cytoplasm at the axon terminal have alot of?

mitochondria.

what is the presynaptic terminal? ( think train terminal )

site where the neurotransmitter releases / travels from.

what does the neuronal cytoskeleton act as??

as scaffolding for cell stability & permits mobility. also plays a role in axonal transport.

what is the membrane potential of the neuronal membrane so important for?

producing an action potential generation & propagation.