KHA258 Lecture Notes - Lecture 2: Globus Pallidus, Meninges, Tegmentum
3 Jul 2018
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Behavioural neuroscience week 2:
2.1: Neurons and glia cells
- Neurons:
oWide variety of sizes and shapes
o“specialized cells for the reception, conduction and transmission of
electrochemical signals”
opyramidal cell is the stereotypical kind,
ocharecteristics of cell body and extensions are present but in different
forms
odifferent functions and different shapes
oanatomy:
ocell body:
cell membrane
properties distinguish it from other cells in the body
whole neuron is contained bag of fluid
odendrite: inputs regions of the neuron
take information from other neurons and translate
if discharges, infortion is sent down
sent to other neighbouring neurons
oaxon:
myelin: individual cells that wrap around the axon
swan cells (glia)
nodes of randia: gaps in axon
oaxon hillock: where body extends onto the axon
oterminal buttons: where axon terminates
boutons
ocomplex internal structure of neurons: not as important as system level
bag of fluid
Cytoplasm: fluid inside the cell
Nucleus: contain DNA of the cell
Instructions to tell cell what to do and how to function
provide information as to how to build itself
Mitochondria: produce energy in form of ADP
helps cell survive and fuction
important in neuron conduction
Endoplasmic reticulum:
extensions from nucleaus
ribosomes (rough or smooth)
golgi complex:
membranes
take neurotransmitters and package them into vesicles
transport down axo
nerve transmitter passed on
oneuronak cekk membrane:
is whaat distinguishes from other cells
bi-lipid membrane (lipid bilayer): two layers of fats
find more resources at oneclass.com
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hydrophilic heads: water living
ooutside layer
Hydrophobic: water hating
oStuck in between layers
Membrane is pose
Allows ions to move in and out of the cell
This allows it electric potential to change
Protein channels:
Embedded proteins
Channels: ions (electrically charged molecules) allowed
to move through
oIons can transport through
Signal proteins:
oNeurotransmitters to modulate internal state of
neuron
oBind on and create change in internal state
oMorphology: different shapes and sizes
several broad classes
Pseudo-unipolar: sensory neurons
Seen in sending projections from surface of skin to
spinal cord
Dentritik tree
Cell body: close to spinal cord
Axon: projects into spinal cord
Synapses with other neurons
One projection that separates with cell body in the
centre
Bipolar neuron:
Retinal cells
Cell body In middle not projected
Axon and dendrite at opposite ends
Multipolar neurons:
Cell body at one end
Many different projections coming off of them (mostly
dendrites)
Other projection is axon
Myelinated neurons tend to be large and project over a large
distance
Short ones usually don’t
Some neurons don’t have projections
Doesn’t have to project over a large distance
- Glial cells: the forgotten cells
oSupport neurons
oRecent evidecen for glial communication
oModulatory effects of glia on neuronal communication
oMore interest being placed onto these cells now
Not just a support, protective, supplying cells
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find more resources at oneclass.com
oCommunicate among selves
oOligodendrocytes:
Extensions ruch in myelin
Create myelin sheaths in CNS
Extensions wrap around cell body of axon
Squeeze intracellualar fluid out of cell
Have fatty tissue wrapped around neuron
Many branches coming off them
oSchwann cells:
Similar functions as other but in PNS
Can guide axonal regeneration
Single cell (not multiple prjections) wraps around axon
Can wrap around neighbouring
oBenefit of fat layer: axonal action potential generation faster
More efficient
Speeds up neural processing
Disease effecting myelin producing is MS
Can happen in CNS or PNS
Slows and leads to an impairment in action potential
production speeds
Impaired neural function
oAstrocytes: largest glia cells
Star shaped
Many functions
Contact capillary, provide pathway for nutrients from
bloodstream to nervous system
Important for bllod brain barrier etc.
Axon communicate among network of cells that can
assist in processing neuron
Linked functioning in astrocytes that simultaneously
operates multiple neuron
Microglia:
Involved in injury or disease
Cleaning up after neuronal death
Break down garbage
No accumulation of junk that would cause problems
- Visualizing neurons:
oStaining
oGolgi stains:
Stain an entire neuron
All projections, cell body etc
Stains only a small proportions of neurons in an area
Randomly stains some but not all
If stained all you wouldn’t see individual neurons
They would be indistinguishable
Only effect 5-10% neurons
Can see neurons in their entirety
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Whole neuron is contained bag of fluid: dendrite: inputs regions of the neuron take information from other neurons and translate if discharges, infortion is sent down sent to other neighbouring neurons, axon: Instructions to tell cell what to do and how to function provide information as to how to build itself. Mitochondria: produce energy in form of adp helps cell survive and fuction important in neuron conduction. Endoplasmic reticulum: extensions from nucleaus ribosomes (rough or smooth) golgi complex: Hydrophobic: water hating: stuck in between layers. Allows ions to move in and out of the cell. This allows it electric potential to change. Channels: ions (electrically charged molecules) allowed to move through: ions can transport through. Signal proteins: neurotransmitters to modulate internal state of neuron, bind on and create change in internal state, morphology: different shapes and sizes several broad classes. Seen in sending projections from surface of skin to spinal cord.
