Neuron Anatomy
Part of the neuron that receives the incoming signals.
Dendrites
what two structures make up the CNS?
brain and spinal cord
during depol, what ion rushes into the neuron?
Na+
PNS cells that form myelin sheath
schwann cells
the part of the brain that is responsible for voluntary movements, behavior, personality, and learning
frontal lobe
dark-staining structures in the neuron cell body that are made of rough ER.
Nissl bodies
This division of the PNS contains the somaic and visceral portions that bring information to the CNS?
sensory pns aka afferent
3Na+ out
2K+ in
Astrocytes
this part of the brain receives somatic sensory info and filters it before going into the cerebrum. It is the reason you are not aware at all times of the clothing on your body or sitting in a chair.
thalamus
the site where action potentials are initiated?
axon hillock
Collections of neuron cell bodies in the CNS are called this.
nuclei
This refractory period prevents any new AP from starting no matter what the stimulus is.
Absolute refractory period
This type of CNS glial lines ventricles and circulates the CSF with long cilia.
ependymal cells
name the three cranial nerves responsible for eye movements. Name and roman numeral
III oculomotor, IV trochlear, VI abducens
What part of the neuron is where the IPSPs are typically located? EPSPs?
the IPSP- axon hillock
EPSP- soma body
What are collections of axons called in the CNS? In the PNS?
nerves in PNS. tracts in CNS
This type of potential occurs on the dendrites and soma and do not travel far?
graded potential, decay due to the leakage of charge across the membrane
if oligodendrocytes were absent of nonfunctional, what would the results be?
slower AP production causing motor and cognitive disfunction (MS).
explain the role of the pituitary gland and its relation to the endocrine system? as well as the hypothalamus?
hypothalamus regulates the release of hormones from the pituitary gland, the pituitary gland releases systematic hormones throughout the body which these hormones then regulate other endocrine glands. (you will learn about this next sem
explain the structural differences in unipolar, bipolar and multipolar neurons:
unipolar- 1 continuous process
bipolar- 2 processes
multipolar- most common in CNS, many dendrites >3 processes
explain the difference in nerves and tracts. What makes axons in the PNS different from the CNS
nerves in the PNS have schwann cells on them and can regenerte
tracts in the CNS oligodendrocytes make up myelin and regeneration is limited
name the two factors that increase conduction velocity and explain how they work?
increased axon diameter-> less internal resistance and faster conduction
myelination-> insulates the axon allowing saltatory conduction between nodes of ranvier which makes AP propagation more rapid
if there were a deficiency in the astrocytes in the CNS, what would the results be?
excess extracellular K+, and neurotransmitter regulation which would cause there to be differences in the excitability of neurons, less support and management of neuronal health
list the three layers of the meninges from outermost to innermost and the function.
pia mater, arachnoid mater, dura mater.
cover and protect, protect BVS, contain CSF, form partitions