Flashcards in Lecture 3 Deck (21):
What is the soma? Name main features.
Soma = nerve cell body
2. Stacks of rER = Nissl bodies
3. Tons of mitochondria
What is the role of dendrites? Name main features.
Expands cell surface area for synaptic input
1. Spines - active structures that change as you learn things
2. No nuclei, BUT mitochondria & rER
What are the characteristics of a chemical excitatory synapse?
Asymmetric pre/post synaptic densities - probably denser post synaptic
What are the characteristics of a chemical inhibitory synapse?
Symmetrical pre/post synaptic densities
Describe an electrical synapse.
Pre and post synaptic sides are connected by gap junctions
Flow of positive ions depolarize neighboring cells
Name the 3 classifications of synapse. (Hint: has to do with where 2 neurons are connected.)
How does the Nissl stain work?
Anulin dye taken up by acidic things
Aka nucleic acids --> ribosomes
Therefore will see Nissl bodies (in neuron cell bodies) because ribosome dense
Don't see axons
What stain do you use to visualize myelin?
Myelin stain black - white matter is black!
Axon in the middle of myelin is white in cross section
What is a neurofibrillar stain?
Stains the axon black
Myelin are white
Opposite of Weigert stain
What is the principle behind the Golgi stain?
Neurons like gold and silver stains
Show dendritic trees
What is the principle immunocytochemisty?
Antigen-antibody reactions so you can visualize nerve cells
Target the specific NT for the neuron you are examining
Describe the 4 features of a retinal ganglion cell.
Multipolar = 1 axon, many dendrites (what you think of)
Describe characteristics of neo-cortical neurons. (6 layers)
Both relay (out of the layers) and interneurons present
Pyramidal and stellate shapes
What are the 2 types of axoplasmic transport?
Axoplasmic transport is transport inside the axon via microtubules
Anterograde = away from soma
Retrograde = towards soma
What 2 proteins are important for axon transport? Name their directionality.
Kinesin - anterograde
Dynein - retrograde
Both use ATP to move along microtubules
What cell myelinates the PNS?
Wraps 1 axon at a time
What cell myelinates the CNS?
Wraps more than 1 axon at a time
What are astrocytes? Name the 2 main types and general characteristics.
= stellate cell bodies + many radiating processes
Fibrous - fewer processes that go long distances
Protoplasmic - many short, branched processes
Role: BBB, metabolic support, NT balance
What are microglia?
Small cells + delicate processes
Respond to injury - proliferate and remove debris in neuro tissue
What is Wallerian degeneration? Can it be overcome?
= distal axon will die if cut away from cell body
Anterograde regeneration = axon will attempt to sprout or regenerate the cut axon if near an oligodendrocyte/Schwarnn