neurons/glia
brain composed of independent cells
signal transmitted from cell to cell across gaps (synapses)
wht r the meninges layers top to bottom
dura, arachnoid, pia
what are the 3 layers and what they develop into
Endoderm- digestive and respiratory tracts
Mesoderm- skeletal system and muscles
Ectoderm- skin and the nervous system (starts as the n
what type of membrane does the neuron have
selectively permeable
What ion is important for neurotransmitter release at the synaptic cleft?
sensory; multipolar
cerebral cortex has how many distinct layers
6
what does the hindbrain develop into
cerebellum, pons, medulla
Na, K, Cl, Ca, large proteins
outside, inside, outside, outside, inside
give me 1 example of a neurotransmitter that causes EPSP and IPSP
EPSP: glutamate
IPSP: GABA
integration zone is at the ____
axon hillock
what is the corpus callosum function
connect right and left brain hemispheres
when does myelination start and when does it continue until
Bonus: where does it begin in the brain and how does it move
3rd trimester and continues throughout adolosecence and early adulthood
- In the brain, starts in the occipital lobes and moves rostrally to the prefrontal
explain how the resting potential is established
Na/K pump
Which glial cell helps with neurotransmitter recycling (gimme an example)
Astrocytes actively participate at the synapse: + Gather glutamate (Glu) from the synaptic cleft + Recycle Glu into its precursor glutamine (Gln) + Returns Gln to the presynaptic terminal for reuse
what are the 4 glial cells found in the CNS and their functions
ependymal: produce csf
microglia: remove cell waste
astrocytes: provide structural support
oligodendrocytes: wrap axons w/ myelin
what causes hydrocephalus
csf circulation failure
where does adult neurogenesis occur
occurs primarily in a region of the hippocampal formation called the dentate gyrus, which is important for memories
what is saltatory conduction
Myelin increases the conduction speed from 1 m/s to over 120 m/s • Potential traveling along the axon jumps from node of ranvier (the gaps between myelin) to node, which is Saltatory conduction
explain ionotropic receptor vs metabotropic receptor
A neurotransmitter may activate an ionotropic receptor (also called a ligand-gated ion channel) at some synapses, opening an ion channel to affect the postsynaptic cell's membrane potential.
The same neurotransmitter may, at another synapse, activate a metabotropic receptor, which activates second messengers (via G proteins) that open other ion channels, and /or cause other changes in the cell.
draw out the nervous system organiztational structure
wht 3 parts make up the brain stem and what are each of their functions?
Pons – contains motor and sensory nuclei to face Medulla - transition of brain to spinal cord, heart rate, breathing
Reticular formation: sleep and arousal, temperature and motor control
what are the 6 stages of neural development and tell me what happens in each
Neurogenesis—mitosis produces neurons from progenitor cells, forming the ventricular zone (250,000 new cells are “born” every minute)
2. Cell migration—cells move out of the ventricular zone toward their destination, where they express particular genes. Radial glial cells help with migration
3. Cell differentiation—cells become distinctive types of neurons or glial cells based on time cellular interactions.
4. Circuit formation- axons of developing neurons grow toward their target cells Growth cones at the axon’s tip guide the axons Synaptogenesis- formation of functional connections (synapses)
5. Cell death- Elimination of excess neurons
6. Circuit pruning- Elimination of excess synapses (synaptic rearrangement): + Active synapses strengthened + Inactive synapse removed
explain all the steps of the action potential and draw the graph
1)Voltage-gated Na+ channels open in response to initial depolarization
2) More voltage-gated channels open and more Na+ ions enter until membrane potential hits +40 mV
3) Voltage-gated Na+ channels inactivation gate closes
4)As inside of cell becomes more positive, voltage-gated K+ channels open
5) K+ moves out of the cells
6) Polarity overshoots beyond the resting potential but restored as K+ channels close
explain wht seizures are and describe the different types
Partial onset
simple partial seizures (normal awareness)
complex partial seizures (awareness impaired)
Generalized onset
absence seizures (petit-mal)
• tonic-clonic seizures (grand-mal)