Nervous Tissue - Fill in the blanks:
The brain and spinal cord comprise the _____ nervous system. All nerves
of the body residing outside of the brain and spinal cord comprise the
_____ nervous system.
Sensory neurons are also referred to as _____ neurons while _____ neurons carry motor impulses. The most common type of neuron is the _____ which communicates from one neuron to another.
The branch of the autonomic nervous system that induces the "flight or fight" response is the_____.
The cells that support, nourish and protect neurons are the _____.
The cell body of a neuron is the _____.
Long extensions off neuronal cell bodies that conduct impulses away from the cell are _____.
The dark granular substance inside neuronal cell bodies are called _____. It is composed of dense collections of _____ where _____ occurs.
_____ are cells that electrically insulate neuronal axons in the central nervous system. This electrical insulation is referred to as _____.
_____ is a CNS disease where the _____ of motor neurons is degenerating or being destroyed, which interferes with neuronal impulses. This is a progressive disease that causes widespread motor deficits.
_____ are specialized epithelial cells in the CNS that produce _____.
In general, positively charged ions are termed _____.
On the inner cell membrane surface of a resting neuron, there is an accumulation of _____ charge.
In electrical terms, "potential" is synonymous with "_____".
An "excitable" cell is one that can quickly and dramatically change its resting membrane potential. Two types of examples of excitable cells include _____ and _____ cells.
The typical neuronal resting membrane potential measures approximately _____.
A neuronal impulse is also referred to as an _____, which indicates that it is a "moving" region of "voltage change" that migrates along the neuronal cell membrane.
There is a greater concentration of _____ions accumulating on the outer surface of resting neuronal membranes than on the inner surface.
The two ways ions may pass across a membrane involve using _____ channels and _____ channels.
The Na/K pump operates by transporting three _____ ions out of the cell while transporting two _____ ions into the cell.
_____-gated ion channels open or close only in response to a change in the nearby membrane potential.
Neurotransmitters bind to specific _____ on the neuronal cell surface. This binding triggers the opening of ion channels that temporarily change the nearby membrane potential. These small, variable, transient changes in membrane potential are referred to as _____ potentials.
When _____ charged ions flow into a neuron, the resting membrane potential becomes less negative.
Voltage-gated _____ channels are triggered to open when the resting membrane potential reaches about _____which is referred to as the _____ potential.
When enough excitatory stimuli act on a neuronal cell, _____-gated Na+ channels on the axon _____ (or "trigger zone") open. Opening of these channels results in the movement of Na+ _____ the cell which causes the inside charge to become more _____.
_____ of Na+ causes _____ of the membrane, which is the first phase of the action potential.
_____ is an example of a drug that block the opening of Na+ channels, thus blocking the initiation of neuronal action potentials.
After the first phase of the action potential, the _____ channels becomes inactivated while the _____ channels begin to open.
This occurs when the membrane potential reaches approximately _____. The opening of these channels results in the _____ movement of _____. This second phase of the action potential is the _____ phase.
The second phase of the action potential ends when the membrane potential reaches about _____ which triggers the inactivation of the _____ channels.
The _____ period of an action potential causes that region of membrane be temporarily unresponsive to another stimulus. This ensures that action potentials migrate in one direction, namely, away from the _____.
Overall, two important factors drive the movement of Na+ and K+ across the membranes. These are the _____ gradient and the _____ gradient.
For any given neuron, all action potentials are of the same intensity. This is referred to as the "_____" principle. In order to alter the intensity of a given neuronal stimulus, the _____ of firing of action potentials is increased.
Action potentials travel fastest in axons that are _____ and _____. The fastest neuronal axon fibers are A-type fibers. These carry _____ and _____ motor signals. The slowest fibers are the C-type fibers. These fibers are _____ and _____ so they transmit action potentials much slower than A-type fibers.
At the axon terminals, voltage-gated _____ channels open in response to the arriving action potential. This triggers _____ vesicles to release _____ into the _____.
Most neurons in the CNS communicate with _____ to _____ other neurons.
The small extensions off of the neuronal cell bodies that receive stimuli are _____.
Small, variable intensity, transient changes in membrane potential that moves the potential closer to threshold are referred to as _____ post-synaptic potentials or "____".
Small variable intensity, transient changes in membrane potential that moves the potential further away from threshold are referred to as _____ post-synaptic potentials or "____".
_____ is a common inhibitory neurotransmitter in the CNS.
Movement of Cl- into a neuronal cell would make a neuron _____ likely to fire an action potential.
Answers:The brain and spinal cord comprise the central nervous system. All nerves of the body residing outside of the brain and spinal cord comprise the peripheral nervous system.