Neurons, and Glia Flashcards
(24 cards)
Neuron
-basic functional unit of the nervous system
-integrates sensory information
-modulates peripheral activity
Glial Cells
-supports brain cells
-provides nourishment and insulation for neurons
Parts of a neuron
-soma
-dendrites
-axon
Soma
-cell body
-contains nucleus, smooth ER, rough ER, Golgi apparatus, mitochondria, and lysosomes
nucleus
houses DNA, controls cell activity
ER
-has many folds
-helps move materials around cells
-processes molecules
Golgi Apparatus
assembles materials from the ER, modifies and packages materials for delivery
mitochondria
produces ATP and helps in cellular respiration
lysosomes
enzymes that break down substances
Cytoskeleton
contains microtubules, microfilaments, and neurofilaments
microtubules
-made of tubulin
-polymerization regulated by microtubule-associated proteins (MAPs)
-Microtubules structurally support the neuron and are the foundation for cargo transport along the axon via dynein and kinesin.
microfilaments
made of actin
forms mesh around membrane
Microfilaments maintain the cell’s shape, guide axon growth, and synapse formation.
neurofilaments
very strong
not hollow
Axon
-unique to neurons and unique to composition
-carries info over distances
-no rough ER
-few free ribosomes
Axon hillock
between soma and axon
action potential occurs here
axon proper
where the action potential propagates
between soma and axon
axon terminal
where neurotransmitters form and are released for synapse
what are the components of the axon terminal and synapse
lots of mitochondria
synaptic vesicles
dense protein filled membrane
no microtubules
how do you get proteins you need to the terminals
material “enclosed” in vesicles walk up and down by kinesin and dynein
kinesin
moves toward the + end of the microtubule
-ATP dependent
-anterograde transport: soma –> terminal
dynein
-retrograde transport: terminal —> soma
-brings damaged organelles and sensory molecules to the soma for repair or degradation
-moves toward the (-) end of the microtubule
dendrites
-receive info from other neurons via synapse
-synapse located in dendritic spines
-contain receptors that bind neurotransmitters
-can be classified by structure, function, or axonal length
Ependymal Cells
help cilia move CSF around, line ventricles up in CNS
-helps form CSF
-gives neuronal stem cells regeneration
Microglia
engulf and degrade damaged neurons
