Cells of the nervous system Flashcards
what are neurons?
excitable cells that conduct impulses.
what method allows us to distinguish between neurons and glia?
the Nissl stain.
what are the 4 major parts of the neuron?
the cell body / soma,
the dendrites, the axon, (considered neurites)
and the presynaptic terminals.
the internal scaffolding / cytoskeleton is made up of 2 micro-what?
microtubules (hollow tubes of tubulin that run longitudinally down neurites) and microfilaments (polymers of actin that run longitudinally and are membrane based).
what are the 3 parts of an axon?
axon hillock,
axon collaterals,
and axon terminals.
the presynaptic terminal consists of what 2 features?
terminal arbour,
bouton en passent.
what separates the presynaptic membrane from the postsynaptic membrane?
the synaptic cleft.
how is the presynaptic terminal cytoplasm specialised?
has no microtubules,
contains synaptic vesicles,
there is a dense covering of specialised proteins,
and there are many mitochondria.
what are the benefits of dendritic spines?
they increase the surface area of the dendrites,
they are plastic - will change structure,
and can isolate chemical reactions so they don’t take place on the whole dendrite.
how do we classify neurons?
by structure and by gene expression.
what are the features of a unipolar neuron?
has a cell body,
this branches and splits into a peripheral process (dendritic process),
and a central process (presynaptic terminals).
what are the features of a bipolar neuron?
has a cell body with a neurite each side,
one projecting away (dendritic process),
and one projecting the other way (presynaptic terminal).
what are the features of a multipolar neuron?
has a cell body with many dendrites attached,
an axon projects from this,
with a presynaptic terminals attached.
what do Astrocytes do?
control the environment surrounding neurons.
where are the brain’s glycogen stores found?
glycogen stores are found within Astrocytes.
