Transcript Nervous Intro.

BIOL 2010 Human Anatomy & Physiology I
What are the functions of the Nervous System?
• _____ ________
(environment & self)
• Conduct ________
• _________
&
__________ impulses
(stimuli)
• __________
What are the functions of the Nervous System?
Out of this comes
_________, & ability
to ___________
How is the Nervous System organized?
________
______ _____
________
______ _____
Central Nervous
System (CNS)
Peripheral
Nervous System
(PNS)
43:
( ___ cranial &
___ spinal nerves)
How is the Nervous System organized?
CNS
____
Afferent
_________
Somatic
____________
Sympathetic
_____________
What are the Structural/functional units
of the Nervous System?
• Nerve cells ~ _______
• Maintaining cells ~
______ ______
Neuron anatomy:
___________________
____________
_________
What are the different types of Neurons?
Structural types: Functional types:
________
______
________
Association ~
Interneurons
Afferent ~ Sensory
neurons
Efferent ~ Motor
neurons
What are the types of glial cells and what
tasks do they accomplish?
___________:
control substances
entering/leaving
CSF
Associated with
_______________
which is formed by
endothelial cells of
blood vessels.
What are the types of glial cells and what
tasks do they accomplish?
_______________:
Line the ventricles
(cavities) of CNS,
create cerebral
spinal fluid and aid
in its circulation.
What are the types of glial cells and what
tasks do they accomplish?
_____________:
Small specialized
macrophages that are
attracted to areas of
damage in the CNS
and phagocytize
debris
What are the types of glial cells and what
tasks do they accomplish?
________________:
Cells in the CNS that
have multiple
extensions that wrap
around multiple
axons forming
myelin sheaths.
What are the types of glial cells and what
tasks do they accomplish?
_______________:
Cells in the PNS that
wrap around single
axons forming
myelin sheaths.
The gaps in between
Schwann cells are
called ______ __
___________
What are the differences between Myelinated
and Unmyelinated Neurons?
_______________:
Action potential
occurs along entire
plasma
membrane…
________
_______________:
Action potentials
jump from one node
to the next…
_________
What is Saltatory Conduction and why is it
important?
Thick myelin
sheaths insulate
plasma membrane
and force “jumping”
(__________)
movement of
electrical charge
(action potential)
____________
effects myelin
sheaths in CNS
How can you tell if nervous tissue is myelinated?
Myelin sheaths contribute
to white appearance =
_____ _________
Neuron cell bodies and
dendrites contribute to a
darker color = _______
__________
Clusters of cell bodies are
called _______ or _____
in the PNS and the CNS
respectively
How are signals sent along the axon highway?
Make sure you are comfortable with:
• Establishment of resting potentials
• Formation and propagation of action
potentials.
• Mechanisms involved with conducting
action potentials between cells
(Intercellular action potential propagation).
How are signals sent along the axon highway?
In addition to
neurotransmitters,
there are also
________________
(w/c influence
_________ of pre- or
post-synaptic
membrane)
Example: ___________, w/c when bound w/
receptors on pre-synaptic neurons limit
neurotransmitter release (see table 11.5)
What is the difference between Excitatory &
Inhibitory neurons?
Ligands binding with postsynaptic receptors can cause:
A _____________ in postsynaptic
membrane potential (_________ ~
closer to zero… depolarization)
Example: ___ ~ opens Na+
channels
An __________ in postsynaptic
membrane potential (_________ ~
further from
zero…hyperpolarized) Example:
________ ~ opens Cl- channels
Are action potentials always propagated
between cells?
Action potentials in pre-synaptic terminal don’t always
result in an action potential on the postsynaptic
membrane…
________ ___________
________ __________
Are action potentials always propagated
between cells?
Different action
potentials from
varying neurons
can
simultaneously
influence the
neuron they
collectively
synapse with to
create ________
___________
How are reflexes and pathways integrated?
___________
Reflexes and
Pathways
___________
___________
Can nervous tissue recover from injury?
Why would the
portion of an axon
severed from the
neuron cell body die?
If a nerve is cut, the ____ ______ and _____ _______ are
phagocytized. However, the Schwann cell bodies remain.
The proximal axon “________” for reconnection
If it encounters ________ _____ then it grows inside this
pathway to re-innervate the organ (muscle)
Why would this not readily occur in the CNS?