Lecture 00 Flashcards
What are the two types of brain cells?
1) Neurons
2) Glia
What are the types of glia?
1) astrocytes
2) oligodendrocytes + Schwann cells
3) microglia
What is the job of a dendrite? (what system is it receiving information from and where does it send it?)
to receive a signal/information from PNS to CNS
what is the job of an axon? (what system is it receiving information from and where does it send it?)
to send a signal/information from CNS to PNS
synaptic ends are also called?
boutons
why does the brain use so much ATP
uses ATP to keep cells at RMP ( 1 ATP is used in every cell for the 3 Na + - 2 K + exchange)
Classifications of neurons are based on?
1) number of neuritis in the body
2) connections
3) dendrites
4) axon length
5) neurotransmitters
types of neurites found in the body
unipolar ex. dorsal root ganglion
bipolar ex. retina
multipolar ex. motor neurons
what type of connections are found between neurons
primary sensory: afferent
motor neurons: efferent
internuerons
remember: ME for motor neurons, then PSA for primary sensory
what types of dendrites
pyramidal v. stellate
spiny v. aspinous
whats so special about spines on dendrites
these spines are small input sites. these sites are where you get changes with learning.
Projection neurons are what type of cells of the cortex?
pyramidal cells
local circuit neurons are what type of cells of the cortex
stellate cells
What role do MAPs play?
microtubule associated proteins are proteins that hold mircotubules together
MAPs and alzheimers?
the proteins become unhinged and accumulate in cell bodies and neurofibulary tangles
Where is the axon hillock located
located right after cell body, very beginning of axon
what happens at the axon hillock?
action potential starts
Which direction does anterograde axonal transport go?
cell body to terminal
which direction does retrograde axonal transport go
terminal to cell body
why is retrograde axonal transport important
send information from axon back to cell
BUT
toxins can also travel to brain i.e. tetanus
ALSO
can use it in scientific experiments to figure out pathway of axons
Functions of astrocytes
- mop up excess K+, prevent cells from depolarizing
- help developing cells migrate to the right areas of the brain
- create scar tissue if theres a brain injury *
- astrocytic feet attach to blood brain barrier capillaries
- if there is too much scar tissue, cancerous tumors can form, astrocytic tumors begin the most common
Oligodendrocytes and Schawan cells make what? and where?
Oligo + Schwann –> myelin sheath
oligo: CNS
Schwann: PNS
Functions of microglia
act as macrophages, clean up waste
i.e. if you have an injury, macroglia become macrophages and clean up da mess
are microglia, glia?
no, not really a glia cell. come form hemotopoetic stem cells (same place blood cells come from) and they can become macrophages
what are circuits
a collection of neurons, have certain fns, and process certain info
what are systems
collection of circuits which are a part of a larger fn
i.e motor, visual, auditory systems
subdivisions of the NS
central and peripheral
divisions of the cns
brain
spinal cord
divisions of brain
cerebrum
cerebellum
brainstem
what is the cerebrum
two hemispheres of brain
what is fn of cerebellum
associated with motor learning and coordination
parts of brainstem
midbrain
pons
medulla
(nerve) divisions of PNS
cranial nerves
spinal nerves
visceral nerves
where do motor axons have their cell bodies
in the CNS
what direction do motor axons travel in
CNS to PNS
where do sensory axons have their cell bodies
in the PNS
what direction do sensory axons travel in
PNS to CNS
what do spinal nerves innervate
skin, joints, muscles
what do visceral nerves innervate
organs, glands, blood vessels
what type of nerves are viscera
ALL motor
what type of nerves are spinal
mix of motor and sensory
what two layers make up the dura mater
periosteal
meningeal
whats a subdural hematoma?
bleeding between dura and arachnoid…creates a space where there should NOT be one
where is the CSF made?
choroid plexus
what are subarachnoid cisterns? where in the brain are they located?
gap between pia and arachnoid where more CSF accumulates
4 dural projections
falx cerebri
falx cerebelli
tentorium cerebelli
diaphragma sellae
fn of falx cerebri
separate cerebral hemispheres
fn of falx cerebelli
separates lobes of cerebellum
fn of tentorium cerebelli
separate cerebellum from cerebrum
fn of diaphragm sellae
opening for pituitary stalk
Parts of the ventricular system (flow of CSF) in order
lateral ventricle 3rd ventricle cerebral aqueduct 4th ventricle central canal
what are the brains foreamen and location
monroe- connects two hemispheres (located in 3rd ventricle)
luschka - 2 of them, run laterally
magendi- 1; goes towards midline
what do nissl stains, stain
stain cell bodies
what do golgi stain, stain
stain myelin sheath ( can see where axons travel)
what level of the nervous system is located above the tentorium cerebella
supratentorial
where is the posterior fossa located
below tentorium cerebelli and above foramen magnum
what are the levels of the nervous system
supratentorial
posterior fossa
spinal cord
peripheral NS
what is found in the supratentorial level of the NS
basal ganglia thalamus hypothalamus CN 1-2 cerebral hemispheres
what is found in posterior fossa level of the NS
midbrain pons medulla cerebellum CN 3-12
