neuron_diversity This interneuron is rat brain, red=glia, blue=DNA.
gradients A^-=other Anions
resting_potential MOST (voltage-gated) are open; K⁺ & Na⁺ channels are closed at rest! Net outflow of K⁺ -> excess anions inside.
action_potential These channels are voltage-gated.
action_potential5 Refractory ensures imodirectional signal.
schwann Myelin (glycolipid) made by glia; oligodendrocytes in the CNS- white matter can regenerate & develop. Demyelination -> multiple sclerosis.
myelin White matter.
===

SQ: 1=c  2=b  3=c  4=a  5=c       7=D
AQ: 1=a  2=a  3=d  4=c  5=c  6=e  7=c  8=d  9=b 10=d
   11=b 12=C 13=d 14=a 15=e
CQ: 1=B  2=C  3=D                           9=C

0. Nerve net: conduct impulses in two directions; one way only postsynaptic cells can bind neurotransmitters
1. Ganglion: cluster of nerve cell bodies outside CNS
2. White matter: CNS axons found in bundles with whitish myelin sheaths.
3. Gray matter: dendrites, unmyelinated axons, neuron cell bodies.
4. Dendrites: Greek dendron, tree.
5. Stretch–gated ion channels sense stretch (mechanically deformed).
6. Ligand–gated at synapses: neurotransmitter
7. Voltage–gated in axons (and in the dendrites and cell body of some neurons) membrane potential changes.
8. Refractory period: Na⁺ channels? inactivation gates remain closed
9. Cerebrospinal fluid drains into veins: nutrients & hormones, remove wastes, cushions by circulating between two of the meninges.
10. Basal nuclei are centers for planning and learning movement sequences
11. Cerebral cortex has a convoluted surface with an additional outer layer of neurons called neocortex: unique to mammals
12. Corpus callosum: thick band of axons, communication between right and left cerebral cortices
13. Somatosensory: body touch, pressure/temp
14. Prefrontal cortex: anterior part of frontal lobes, in front of motor and premotor areas.
    Executive Function: decision, prediction, plan, goals.
15. Blood-brain barrier: tight junctions in brain blood vessels allow lipid-soluble (O₂, CO₂), prevent infections, non-steroid hormones.
16. Roger Sperry: Nobel 1981 right/left brain.