Chapter 11 A BSC 2085 Class Notes Fall 2010
The Nervous System is the _________________ and __________________system of the body.
Its cells communicate by _______________ and _______________ signals that are rapid and specific,
1 and usually cause an __________________ response.
What are the 3 Main Functions of the Nervous System?
What are the 2 Main Divisions of the Nervous System? Please describe 3 characteristics of each:
(Slides 8-9) Please describe the 2 Functional Divisions of the Peripheral Nervous System:
(Slides 10-11) Please describe the 2 PNS Motor Divisions:
(Slide 12) Please describe the 2 functional subdivisions of the Autonomic Nervous System:
Describe the 2 main types of cells in the Nervous System:

(Slide 15) Please name 6 types of neuroglia cells and indicate if they are in the CNS or PNS:
What is the most abundant neuroglia?
(Slides 16-17) What are 5 functions of Astrocytes?
What is the main function of the microglia?
Where can ependymal cells be found?
What is the function of oligodendrocytes?
Where can you find satellite cells?
What is the function of Schwann cells?
(Slide 27) What are 3 special characteristics of neurons?
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What is the major function of the plasma membrane of neurons?
The cell body is the _______________ center of a neuron.
The _____________________ is a cone-shaped area from which the axon arises.
Clusters of cell bodies are called ________________ in the CNS and ______________ in the PNS.
_______________ of neurons receive incoming chemical signals, and _______________ of neurons send outgoing Action Potentials.
Bundles of neuronal processes are called __________ in the CNS and __________ in the PNS.
________________ are the Receptive (input) region of a neuron.
(Slide 33) Dendrites bind _______________________ that were released from the ________ of a communicating neuron.
Based on information from the neurotransmitters, dendrites send electrical signals toward the neuronal cell body in the form of ________________________________. These are not
_________________________________________.
_____________ axon per cell arises from the axon hillock.
(Slide 36) The end of the Axon can have 10,000 or more branches called ________________________.

Knoblike ______________________________ at the very end of each axon are also called
_______________________ or ________________(French for button)
The axon ____________________ is the secretory region of neuron that releases neurotransmitters to excite or inhibit other cells.
The main function is the Axon is that it is the _______________________ of a neuron.
The Axon generates and transmits nerve impulses called _______________ away from the neuronal cell body.
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(Slides 38-39) Molecules and organelles are moved along axons by motor molecules in these two directions:
How are myelin sheaths formed?
What are the main functions of the myelin sheath that wraps around the axon?
What is the neurilemmea?
During _______________________________ the Action Potential appears to “jump” from one
_________________________________ to the next. This is called ___________________________ conduction.
How much faster is Saltatory Conduction in comparison to conduction at unmyelinated axons?
Why is it faster?
(Slide 46) What cell accomplishes myelination in the CNS?
Are Nodes of Ranvier created by this type of myelination?
Please briefly define White Matter and Gray Matter.
Describe the 3 Structural types of Neurons:
(Slide 53-54) Describe the 3 functional types of Neurons:
Go to Slides in Chapter 11 part B
Neurons are highly irritable or _____________________ to a stimulus. Neurons respond to an adequate stimulus by generating an ______________________. This __________________ is always the
_________________ for any size of stimulus.

What are the two types of gated ion channels in a neuronal membrane?
(Slide 6) Membrane potentials (localized voltage) act as ________________ in the nervous system.
Membrane potential changes when _______________________ of ions across the membrane change, or when ______________________________ of the membrane to ions changes. Changes in membrane potential are signals used to ____________, ____________________ and _____________ information.
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(slide 7) What are the two types of membrane potentials and please briefly describe them?
Graded potentials are _________________, ____________________ changes in the membrane potential.
Graded potentials can be __________________or _______________________.
The ___________________ of a graded potential varies directly (is graded) with stimulus strength.
(Slide 10) The _________________________ is a brief reversal of membrane potential with a total amplitude of ~100 mV. It occurs in ___________________ and the ________________ of neurons.
The _______________________ does not decrease in magnitude over distance, and it is the principal means of long-distance neural communication.
Please Label the Figure Below

(Picture Slide 11) What is the Resting Potential of a Neuron? Is it positive or negative?
What is the threshold voltage for triggering an Action Potential?
What is the average voltage an Action Potential generates on the inside of the axon membrane?
Is it positive or negative?
(Slide 13) Describe the resting phase:
(Slide 14) What events cause depolarization?
(Slide 15) What events cause repolarization?
(Slide 16) Which channel is responsible for hyperpolarization?
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(Slide 18) What restores the areas near axon membrane to their original ionic concentrations?
(Slide 20) The action potential spreads in ______________ (one or two?) direction(s).
(Slide 24) Since all Action Potentials are exactly the same, how does the CNS tell the difference between a weak stimulus and a strong one?
Slide 25, 27) An action potential ______________ be triggered during the absolute refractory period, but can be triggered during the ____________________________ if the stimulus is
___________________________.

(Slide 29) _____________________________ is an autoimmune disease in which myelin sheaths in the
CNS become nonfunctional ________________________ (hardened). _________________ and
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_______________________ of nerve impulses occurs, and impulse conduction slows and eventually
________________.
(Slide 30) Some immune system–modifying drugs, including __________________ and
_____________________ hold symptoms at bay, reduce complications, reduce disability.