Download Biology 4 Study Guide

Name _____________________________________________
Period ______
Date _______________________
Anatomy Study Guide
Chapter 11: “Nervous & Nervous Tissue”
Functions & Divisions of the Nervous System
There are 3 functions of the nervous system: 1) It collects __________ input which is information about the
internal & external ____________ and is gathered by ____________ receptors; 2) ________________ is the
__________________ of that sensory input gathered by the receptors; and 3) It provides a ____________
output by way of the activation of _____________ organs (____________, glands, etc.)…ultimately it’s the
production of a _____________.
There are 2 major divisions of the nervous system: 1) The __________ nervous system (_____) is composed
of the __________ & the ________ _______ and serves as the body’s _______________ & ___________
center; while the 2) ______________ nervous system (_____) is composed of the _________ & __________
nerves and carries ____________ to and from the ________. The peripheral nervous system is divided into
two ____________ divisions: a) the sensory (___________) division is able to ________ information _____
the CNS from the ____________ organs and the b) motor (____________) division is able to __________
information _______ from the CNS to ____________ organs. The motor division is then further divided
into the somatic (______________) nervous system which provides _____________ control of skeletal
muscles and the autonomic (________________) nervous system which regulates ___________ muscle,
___________ muscle, and the __________. The autonomic system is divided into the ________________ &
the _________________ systems.
Histology of Nervous Tissue
Neurons (aka “_______ ______”) are the fundamental units of the __________ __________. They are cells
that are capable of carrying ____________ __________. All neurons have 4 special characteristics: 1) They
are _____-lived (some capable of living ____ years or more!); 2) They are amitotic which means they cannot
________ (with a few exceptions); 3) They have a high _____________ rate (and require a continuous ____
& ________ supply); and 4) Their plasma membranes are designed for ____________ _____________.
Typical neurons are composed of 4 distinct regions:
1. _____________ are the parts that _____________ & ______________ to the signals from other
neurons. They use special _______________ that are able to respond to ____________________.
Their other function is to deliver an _______________ __________ to the cell body of the neuron.
2. The ________ ________ (aka “_____________” or “_______”) is the neuron’s _________________
center. It takes all ____________ electrical signals & _____________ them. If the incoming signals
are ___________ enough, then the cell body allows that signal to _____________ to the _________.
3. The _______ is a long, thin __________ that makes neurons the _______________ cells in the body.
It carries the _______________ __________ away from the cell body, and is what allows signals to
be carried ________ _____________. Multiple _______ are bundled together to form “_________”.
4. ____________ terminals are the endings of the _______. They contain ________________ (NTMs).
They release the NTMs to other ____________, ___________, or ____________.
Other cells of the nervous system:
The word _____________ literally means “___________ _______”. These are cells that ____________ the
_____________ of the nervous system but are not capable of carrying ________________ _____________.
Some of these cells are only found in the ______________ Nervous System:
1. _________________ are abundant, _______-shaped cells that ____________ neurons & control the
______________ environment of the brain. They form a _____________ between the
________________ & the ___________.
2. _______________ are ____________-like __________________ that dispose of ______________.
3. __________________ cells line the _______________ of the brain & the spinal cord. They help to
circulate the ______________________ ___________.
4. ____________________ produce a _____________ sheath around the ____________ ____________
in the ____________ nervous system only.
*The _____________ sheath acts like _________________ & prevents ___________ ____________.
Some of these cells are only found in the __________________ Nervous System:
1. ______________ cells protect the ______ ________ of the neurons in the peripheral nervous system.
2. ____________ cells form the ___________ sheath around the _________ in the PNS. They are also
vital to the ___________________ of ______________ peripheral nerves.
*The myelin sheath of the PNS is formed in a “__________ ______”-like fashion. It ______________ the
axons & _____________ the electrical __________. The Nodes of ____________ are small ________ in
the ____________ sheath that are formed by the __________ between the _______________ cells.
Structural Classification of Neurons:
1. _______________ neurons are characterized by _______ ______________ from the cell body. All
of these neurons are ___________ neurons.
2. ____________ neurons consist of only one _____________ & one _________. They are found only
in the __________ (receptors for _________) & in the ________ (receptors for __________).
3. ______________ neurons consist of a _________, _________ ________________ leaving the cell
body. All of these neurons are _____________ neurons
Neuron Function & Action Potentials
Information Processing Requires 4 Basic Operations:
1. Must first _____________ the ________ of stimulus. These are distinguished by _______________
_____________ _____________ in the brain.
2. Must determine the _____________ of the stimulus either by the ___________ of _________ a
____________ neuron “_________” or by the __________ number of neurons “firing” ___ _______.
3. Must ____________ the information from many different ________________.
4. Must ____________ & ____________ a response.
Basic Neuron Function:
Neurons are highly ____________ (meaning they are responsive to ____________), and they are adapted to
send ________ over long distances by generating “________ ___________”. An action potential is basically
a “_________ ___________”…a brief change in the _____________ __________ found on either side of the
never cell _____________. The action potential travels from the ________ _________ to the end of the
_________ and is always the same ____________ regardless of the ______________. Action potentials are
created by the movement of _____________ charged ___________ & ____________ ions across the cell
membrane of the _______. As the charged ____________ move, they create electrical ____________. This
is considered an “____-or-_____ phenomenon” as it either happens _______________ or _____ ___ ______.
The threshold stimulus represents the ____________ stimulus required to create an _________ __________.
Conduction ___________ is the __________ that action potentials travel. The velocities may vary widely
with some being _________ than others. However, the _____________ generally occur at _____ meters/sec
or more! The rate is determined by a couple of factors. The first is the axon ___________. Axons with
larger diameters have ____________ ______________ ______________. The second factor is the degree of
_______________. Axons with more ___________ will have faster conductions velocities as well.
The Synapse & Neurotransmitters
Synapses are __________ that __________ information between two neurons. They are also found between
__________ & ___________ cells/organs. The ______________ neuron conducts impulses __________ the
synapse while the ________________ neuron conducts the impulses ________ from the synapse. The two
most common types of synapses are the axodendritic and axosomatic synapses. The ________________
synapse is found between the _______ of one neuron & the ____________ of another. The _____________
synapse is found between the _______ of one neuron & the ______ _________ of another. Both of these
may either be an “____________” or a “____________” synapse.
Electrical synapses are not as common as ____________ ____________. In this case, the neurons are
______________ connected to each other by way of _______ junctions. The ______________ signal travels
___________ through the _______ junctions. They are very _________ & are utilized to help complete very
________ events (for example, ____________).
Chemical synapses are specialized for ___________ & ___________ neurotransmitters. They are typically
composed of two parts: 1) The _______ __________ is found on the ______________ neuron & contains
synaptic ___________ with __________________ inside of them. 2) The ____________ region is found on
the ________________ neuron & has special receptors that ___________ ___________________. The
synaptic cleft is the _________-filled space between the presynaptic & postsynaptic neurons. It prevents
__________ ___________ from _____________ passing from one neuron to the next. The transmission of
an electrical impulse between neurons is fairly simple. When the electrical __________ reaches the end of
the axon, ___________________ are _____________ from the _______________ terminals. The NTMs
then _____________ through the synaptic ___________ & ________ to receptor sites on _______________
________________. Terminating the effects of the neurotransmitters occurs within a ______ milliseconds
of their __________ from the axon terminal. This termination happens as a result of either the NTMs being
____________ ________ by enzymes, being _________________ into the axon terminal, or by __________
away from the synaptic cleft.
Types of neurotransmitters:
Most neurons make ___ or ______ neurotransmitters at any one time. The number of _____ per _________
that a neuron “_________” determines which neurotransmitter is actually ______________. There are over
_____ different NTMs that have been identified. Below are 6 of the more common ones in the human body:
Neurotransmitter
Some Functions
1)
Activate ________________ muscles
2)
Important in _______________ _________________
3)
Activates organs of __________________________ nervous system
4)
Influences _____________ (“______________” feelings) & ______________
5)
Influences _____________ (“________ ________”) & reduces ___________
6)
Important in forming ___________________
Neuronal Integration…Circuits
There are 3 main kinds of circuits in the nervous system: diverging, converging, & reverberating.
______________ circuits are composed of _______ incoming nerve fiber that stimulates __________ fibers.
It often acts as an “_______________” circuit. An example would be a _________ neuron in the brain that
can activate _____________ of motor neurons in the spinal cord and ultimately ______________ of skeletal
muscle fibers. ______________ circuits are composed of _____________ nerve fibers in different areas that
combine their signals into _____ fiber. They often have a “________________” effect and lead to either
strong _______________ or strong _____________. An example would be __________ a baby smile while
_________ baby powder & ___________ the baby laugh. All of these __________ to trigger “warm/fuzzy”
feelings for the parents. _______________ (oscillating) circuits are a chain of neurons arranged in a ______
that results in a signal that is sent through the circuit ______ & ______ in a ___________ pattern. Examples
would include the ________-______ cycles, breathing, & arms _____________ when walking.
Processing information in the nervous system:
___________ processing is when the input travels along ____ ______ to a ___________ destination. It
works in an all-or-none manner producing a specific ______________. An example would be the spinal
____________. A ___________ is considered the _____________ behavior. It is an _________________
movement of a body part in ______________ to a stimulus. It occurs without involving the _____________
__________ of the brain. In this case, the signal is sent to the ________ ________ & immediately back to
the ________. This usually occurs in order to help keep you from __________ _________.
___________ processing is when the input travels along _________ ___________. In this case one _______
promotes many __________. This type of processing is crucial for _________-level ________ functioning.
An example might involve the senses. A __________ usually isn’t processed as just an ________. It usually
also triggers ____________ of experiences associated with that ___________.
Homeostatic Imbalances
1. Multiple ____________ (MS) - an _______________ disease that mainly affects _________ adults.
With this disorder, the _________ sheaths in the CNS are destroyed as they turn into ____________,
hardened lesions. This leads to ________-___________ of the nerve impulses & eventually the
impulse conduction _____________. The symptoms include visual & _________ disturbances,
general weakness, loss of _________ control, & loss of __________ control.
2. Neuroblastoma – a ____________ tumor that occurs in the ______________ nervous system of kids.
3. Rabies – a _______ infection of the nervous system. It is transmitted through _______ from infected
animals & causes inflammation of the _______, _____________, & ultimately __________.
4. Shingles – viral infection of the _________ neurons of the skin. Results in scaly, painful _________
that are similar to ____________ but with pain. This is seen mostly in adults over _____ years old.