Humans are the species with the most neurons? T/F
Humans have 1 billion
Elephans have 2 billion
FALSE
range of neurons in the brain
15-30 billion
How to determine the number of synapses we have.
How does the size of synapses range?
the number of seconds in 10 billion years.
3 ft. in length
3 parts of a neuron
dendrite, cell body, axon
Glial cells outnumber neurons _:1
9:1
what components of nervous tissue are gray matter, or white matter?
Gray: nucleus, dendrite, ganglia
White: Axons, myelin
Interneurons are located where?
Entirely within CNS
“middle man” that lives within grey matter
Define Microglia
type of macrophage that destroys invasive microorganisms
Define Astrocytes
most abundant glial cells, help c nutrition & act as antigen presenting cells for WBC
most abundant glial cell type is:
Astrocytes
Define Ependymal cells
semi-permeable lining that has cilia to circulate CSF
___ forms myelin sheaths
Oligodendrocytes
2 glial cells of PNS, and their function.
Schwann cells: similar to Oligo..for myelin and microglia by engulfing cell debris
satellite cells: surround & maintain cell bodies in ganglia
Neurons get close, but do not touch each other (other than dendrites), how do they communicate at the terminal axon?
Using neurotransmitters at the terminal axon
the NT binds to postsynaptic receptor which releases other ions. Ultimately this causes a postsynaptic action potential, aka “impulse”
2 most important NT’s
acetylcholine and norepi
What are the following drugs’ effect on the neuromuscular junction?
Botulinum Toxin (aka “Botox”)
Succinylcholine (aka “Sux”)
Rocuronium (aka “Roc”)
These are all paralytics, but work differently
How does Botulinum (Botox) toxin work?
presynaptic intracellular blockade of acetylcholine secretion- does not pass BBB, but if inject into venous system lungs will arrest
How does Succinylcholine (Sux) work?
only depolarizing agonist of acetylcholine. not degraded by acetylcholinesterase; first causes fasciculations, then paralysis (sux it out)
How does Rocuronium (Roc) work?
nondepolarizing, competitive antagonist of acetylcholine at post synaptic cleft can be used to dx: myasthenia gravis
5 functions of the brain’s Frontal Lobe
Thought Voluntary movement Executive functions/problem solving Speech production - broca's area Personality/emotions/self-control
__ lobe is Executive. In charge of major thoughts & voluntary movements including speaking.
Frontal lobe
A stuttering problem can be damage to:
Broca’s area
5 functions of Parietal lobe
Sensation Speech comprehension- Wernicke’s area Spacial recognition Reading/Spelling Arithmetic
Frontal lobe has __ actions, whilst
Parietal lobe has __ actions
Frontal lobe: motor actions
Parietal lobe: sensory actions
3 functions of temproal lobe
Hearing
More Memory(also in Frontal lobe)
Behavior
Primary function of occipital lobe…
vision
3 functions of Cerebellum
Balance
Coordination
Fine muscle control