Nervous system (lab) Flashcards
Central Nervous System
brain and spinal cord, processes info
Peripheral Nervous System
cranial and spinal nerves, transmits info
PNS divided into
Sensory (afferent, input), motor (efferent, output)
Motor neurons divide into
autonomic (organs and glands) and somatic (to skeletal muscles)
Sensory neurons divide into
somatic (from skin) and visceral (from organs and glands)
Autonomic motor neurons divide into
sympathetic (fight or flight) and parasympathetic (rest and digest)
Neural tissue derived form
ectoderm
cell body contains
nucleus, rough ER (Nissl bodies), organelles, neurotransmitter synthesis
dendrites
projections from cell body or at end of axon, receive signal,
axon
long extension, ions for signal transmission, electrically insulated by myelin
nodes of Ranvier
intervals where myelin is interrupted on along axon, regular intervals
myelin
fatty sheath that insulates
synaptic vesicles
on axonal terminals, release neurotransmitter
axon hillock
where axon meets cell body
nerve
bundle of axons in PNS
white matter
bundles of axons in the CNS
appears white due to
myelin around axons
gray matter
clusters of cell bodies in CNS (unmyelinated)
ganglia
clusters of cell bodies in PNS
biggest part of brain
cerebrum
cerebral cortex
outer bark of folded gray matter (clusters of cell bodies)
subcortical gray matter nuclei
islands of gray matter deep within brain
cells of neural tube become
CNS
neural crest cells
some cells break away from neural folds, will form portions of PNS
organization similar
muscles: endoneurium, perineurium, epineurium
multipolar neuron
dendrites on cell body, axon at end of process, abundant in CNS
bipolar neuron
cell body in center, flat, dendrites and axons at end of processes on either side, special senses, receptive zone until other side of cell body
unipolar (pseudounipolar) neuron
cell body in center, raised, axons and dendrites at ends, conductive some length of projections, abundant in PNS
astrocytes
CNS, blood/brain barrier, provides nutrients and support to neurons, most abundant, guide neural development, damage repair, 3D framework, recycle neurotransmitters
oligodendrocytes
CNS, myeliantes neurons of CNS, multiple per oligodendrocyte
microglia
CNS, immune cells of CNS, attack pathogens, remove neuronal debris, migrate through neural tissue
ependymal cells
CNS, make cerebrospinal fluid, lines CNS cavities, moves CSF (some ciliated/microvilli
schwann cells
PNS, myelinates neurons of PNS, one neuron per schwann cell
satellite cells
PNS, surrounds neuron, provides nutrients, controls environment
neural plate becomes
neural groove
neural folds
raised edges of neural plate
neural fold meet to form
neural tube
notochord
rod of mesodermal tissue under neural plate, will become vertebral column
3 primary brain vesicles from anterior neural tube
prosencephalon (forebrain)
mesencephalon (midbrain)
rhombencephalon (hindbrain)
secondary brain vesicles from prosencephalon
telencephalon, diencephalon
secondary brain vesicles from mesencephalon
mesencephalon
secondary brain vesicles from rhombencephalon
metencephalon, myelencephalon
adult brain structures from telencephalon
cerebrum, lateral ventricles
adult brain structures from diencephalon
diencephalon (thalamus), third ventricle
adult brain structures from mesencephalon
brain stem: midbrain; cerebral aqueduct
adult brain structures from metencephalon
brain stem: pons, cerebellum; fourth ventricle
adult brain structures from myelencephalon
brain stem: medulla oblongata; fourth ventricle
spina bifida
incomplete closure of neural tube
Dura mater
Outer layer of spinal cord
Arachnoid mater
Middle layer of spinal column protection
Pia mater
Inner layer of spinal cord protection
Graded membrane potential
Due to ionic movement across cell, dies out as it spreads away from initial site
Action potential
Predictable change in transmembrane potential due to opening of specific voltage gates channels
Threshold
Membrane potential value that opens voltage gates channel
2 factors that affect velocity of action potential
Diameter, myelinated or not
As diameter of axon increases
Velocity of action potential increases
Saltatory conduction
Jumping effect of AP from nodes of ranvier
A fibers
Largest diameter, myelinated, fastest
B fibers
Medium diameter, myelinated
C fibers
Smallest diameter, unmyelinated, slowest
Inhibitory signal
Generate hyperpolarizing graded potentials
Excitatory signal
Generate depolarizing graded potentials
Spatial summation
Single post synaptic neuron receives signal from many pre synaptic. Transmembrane is combination of all
Temporal summation
Only 2 neurons communicate, release neurotransmitter repeatedly and builds