Transcript of the spinal cord.

Nervous System
Bell Ringer
Describe the kinds of
things that you think
could slow down
response time of
your nervous system.
Central Nervous System
Focus Questions
How is the nervous
system organized?
What is the physiology
of nerve impulses?
What is a reflex arc?
What are the
functional areas of the
brain?
What are the two
functions of the spinal
cord?
What are the major
disorders of the CNS?
Central Nervous System
Objective
Describe how the
nervous system is
organized.
Identify the different
types of support cells in
the central nervous
system and their
functions.
Nervous System Organization
The nervous system is divided into
two parts:
1. Central Nervous System (CNS)
•Brain and spinal cord
2. Peripheral Nervous System
(PNS)
•Cranial nerves, spinal nerves,
peripheral nerves, and ganglia.
Nervous System Organization
Principal cell types – supporting
cells and neurons.
•Supporting cells of the CNS are
known as the neuroglia (nerve glue).
• Do not transmit nerve impulses.
• Neuroglia never lose their ability
to divide. Because of this, most
brain tumors (gliomas) are formed
by neuroglia.
Types of neuroglia (glia)
Astrocytes
•Star-shaped cells
•cling to neurons and anchor them to
capillaries.
•role in nutrient exchange
•protects neurons from harmful substances
in the blood.
•helps to control the chemical environment
in the brain.
Types of neuroglia (glia)
Microglia
•Spider-like phagocytes. Dispose of
debris such as dead brain cells and
bacteria.
Ependymal
•Line the cavities of the brain and spinal
cord. Cilia beat to help circulate the
cerebrospinal fluid.
Central Nervous System
Objective
Describe how the
nervous system is
organized.
Identify the different
types of support cells in
the central nervous
system and their
functions.
Slide
8 of 33
End Show
Bell Ringer
Why do you think exposure to
toxins have more devastating
effects during early pregnancy
than in late pregnancy?
Copyright Pearson Prentice Hall
Central Nervous System
Objective
Describe the
locations and
functions of the soma,
dendrites, axon, axon
terminals, synaptic
cleft, myelin sheath,
and nodes of Ranvier.
Explain how a
homeostatic
imbalance of the
myelin sheath leads
to multiple schlerosis
.
Types of neuroglia (glia)
Oligodendrocytes
•
Wrap around nerve fibers. Produces
fatty insulated covering called the
myelin sheath. (CNS only)
Bell Ringer
Mrs. Albertson, a new mother, brings her infant to
the clinic because he has suffered repeated seizures.
Upon questioning, she states that her labor was
unusually long and difficult. What might be the
problem?
Bell Ringer
Answer each of the following:
Think of any given cell in the
body. What role does it play?
What goes on inside your body
during running or other sports?
How do cells help you in sports?
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Central Nervous System
Objective
Describe the soma, dendrites, axon,
axon terminals, synaptic cleft,
myelin sheath, and nodes of
Ranvier by creating analogies.
Explain how a homeostatic
imbalance of the myelin sheath
leads to multiple schlerosis .
Explain how the sodiumpotassium pump creates action
potential.
Agenda
•Bell Ringer
•Standard & Objectives
•Lesson – Neuron structure
• Activity – Neuron illustration
•Conclusion - Q&A and exit cards
Neurons
Nerve cells that are highly specialized to
transmit messages are known as neurons.
Bell Ringer
Mr. Dingledine is an 82-year old
bedridden gentleman who has
discovered a new interest in learning
about his body. While being attended by
the visiting nurse, he remarks that the
supporting cells in nervous tissue (such
as oligodendrocytes) act like rubber
coating around household wiring. What
does he mean by this analogy?
Copyright Pearson Prentice Hall
Neurons
Neuron part
Function
Soma (Cell
Body)
Dendrites
Contains the nucleus but no centrioles.
Metabolic center of the cell.
Receive and conduct impulses toward the
cell body.
Generates impulses and transmits them
away from the cell body.
Branches at the end of the axon. Has
hundreds of vesicles containing
neurotransmitters.
Axon
Axonal
terminals
Neurons
Neuron part
Function
Synaptic Cleft Tiny gap that separates neurons.
“Synapse”
Myelin sheath Covers nerve fibers, insulating them and
increasing the transmission of nerve
impulses. In the CNS, the myelin sheath is
produced by oligodendrocytes instead of
Schwann cells. Due to this, nerve fiber
regeneration is mostly lacking in the CNS.
Nodes of
Gaps/indentations in the myelin sheath
Ranvier
between the oligodendrocytes.
Neuron Labeling
Soma (Cell Body)
Dendrites
Nucleus
Axon
• Unipolar
• Bipolar
• Multipolar
Schwan Cell
Myelin Sheath
Node of Ranvier
Terminal
Axons
Nucleus
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Central Nervous System
Objectives
Explain how a homeostatic imbalance of the
myelin sheath leads to multiple sclerosis .
Differentiate between irritability and conductivity
in neurons
Identify the essential ions that are part of nerve
cells
Explain how the sodium-potassium pump
generates action potential
Agenda
•Bell Ringer
•Standard & Objectives
•Lesson – Neuron physiology
• Activity – Modeling Action Potential
•Conclusion - Q&A and exit cards
Homeostatic Imbalance
Multiple Sclerosis (MS) – An autoimmune disease
where the myelin sheath is gradually destroyed.
This leads to the current in the nerve cells being
short-circuited and the person loses the ability to
control their muscles.
Physiology of the Nervous System
Two major functional properties of neurons:
• Irritability – ability to respond to a stimulus and
convert it into a nerve impulse.
• Conductivity – ability to transmit the impulse to
other neurons, muscles or glands.
Physiology of The Nerve Impulse
Important ions of the nervous system:
___________________ Ions (K+)
___________________ ions (Na+)
The Nerve Impulse
The sodium-potassium pump in the nerve
cell membrane pumps sodium (Na+) ions
out of the cell and potassium (K+) ions into
the cell by means of active transport.
As a result, the inside of the cell contains
more K+ ions and fewer Na+ ions than the
outside.
Sodium Potassium Pump
For every three Na+ pumped out of the cell, only
two K+ ions are pumped inside. This causes
there to be a slightly negative charge inside the
cell and a slightly positive charge outside the
cell when it is in a resting state. This is called
the resting potential.
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The Nerve Impulse
• Sodium-Potassium Pump
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Bell Ringer
Based on what you’ve learned about
neurons so far, why are sports drinks
high in potassium and sodium salts?
Hint: Look
at your
notes from
yesterday.
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Bell Ringer
A brain tumor is found in a CT scan of
Mr. Childs head. An exhaustive workup
has revealed no signs of cancer
elsewhere in Mr. Childs body. Is the
brain tumor more likely to have
developed from the neurons in the brain
or from the neuroglia? Why?
Copyright Pearson Prentice Hall
Wrestling Activity Schedule
8:30 – 9:24
First Period
9:29 – 10:23 Second Period
10:28 – 11:22 Third Period
Fourth Period
11:27 – 12:22 4A Class (lunch 12:22 – 12:47)
11:52 – 12:47 4B Class (lunch 11:22– 11:47)
12:53 – 1:47
Fifth Period
1:52 – 2:46
Activity
2:51 – 3:45
Activity
32
Central Nervous System
Objectives
1) Describe how neurons transmit a nerve
impulse through depolarization and
repolarization of cell membrane.
Visualize IT!
Nerve Impulse Animation
Sodium-Potassium Pump
(Resting Potential)
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The Nerve Impulse
The Resting Neuron
Polarized: In the resting (inactive) state there
are fewer positive ions on the inner face of the
neuron’s plasma membrane than there are on
its outer face in the tissue surrounding it.
Na+
+ + +
+ + + + ++
- - - - - - - - +
K+
- - - - - - - - -
+ +
+
+ + + + ++ + +
The Nerve Impulse
The Moving Impulse
An impulse begins when a neuron
is stimulated by another neuron
or by the environment.
The Nerve Impulse
At the leading edge of the impulse, gates in
the sodium channels open allowing
positively charged Na+ ions to flow inside
the cell membrane.
The Nerve Impulse
The inside of the membrane
temporarily becomes more positive
than the outside, reversing the resting
potential.
The Nerve Impulse
This reversal of charges is called a
nerve impulse, or an action potential.
The Nerve Impulse
As the action potential passes, gates in the
potassium channels open, allowing K+ ions
to flow out restoring the negative potential
inside the axon.
The Nerve Impulse
The impulse continues to move along
the axon.
An impulse at any point of the
membrane causes an impulse at the
next point along the membrane.
Visualize IT!
Nerve Impulse Animation
Action Potential
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Knowledge Check
How many Na+ are pumped out
of the neuron?
A) 1
B) 2
C) 3
D) 4
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Knowledge Check
How many K+ are pumped into
the neuron by the sodium
potassium pump?
A) 1
B) 2
C) 3
D) 4
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Knowledge Check
Generates the impulse and
transmits it away from the cell
body
A) Dendrites
B) Soma
C) Axon
D) Myelin Sheath
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Knowledge Check
The metabolic center of the
neuron
A) Dendrites
B) Soma
C) Axon
D) Myelin Sheath
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Knowledge Check
Insulates the neuron so that it
doesn’t short out
A) Dendrites
B) Soma
C) Axon
D) Myelin Sheath
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Central Nervous System
Objectives
1) Describe how neurons transmit a nerve
impulse through depolarization and
repolarization of cell membrane.
The Nerve Impulse
Threshold
• A stimulus must be of adequate
strength to cause a neuron to
transmit an impulse.
• The minimum level of a stimulus
that is required to activate a
neuron is called the threshold.
The Nerve Impulse
• A stimulus that is stronger than
the threshold produces an
impulse.
• A stimulus that is weaker than
the threshold produces no
impulse.
The Synapse
The Synapse
• At the end of the neuron, the
impulse reaches an axon terminal.
Usually the neuron makes contact
with another cell at this site.
• The neuron may pass the impulse
along to the second cell.
• The location at which a neuron can
transfer an impulse to another cell is
called a synapse.
The Synapse
• A Synapse
The Synapse
The synaptic cleft
separates the axon
terminal from the
dendrites of the
adjacent cell.
Synaptic cleft
Terminals contain
vesicles filled with
neurotransmitters.
Neurotransmitters
are chemicals
used by a neuron
to transmit an
impulse across a
synapse to
another cell.
The Synapse
Vesicle
Neurotransmitter
• As an impulse
reaches a
terminal, vesicles
send
neurotransmitters
into the synaptic
cleft.
• These diffuse
across the cleft
and attach to
membrane
receptors on the
next cell.
The Synapse
Receptor
The Synapse
Sodium ions then rush across the membrane,
stimulating the next cell.
If the stimulation exceeds the cell’s threshold, a
new impulse begins.
The Synapse
Moments after binding to receptors,
neurotransmitters are released from the cell
surface.
The neurotransmitters may then be broken down
by enzymes, or taken up and recycled by the
axon terminal.
35-3 Divisions of the Nervous System
The human nervous system has
two major divisions:
a. central nervous system
b. peripheral nervous system
The central nervous system
relays messages, processes
information, and analyzes
information.
a.The central nervous system
consists of the brain and the
spinal cord.
b. Both the brain and spinal cord are
wrapped in three layers of
connective tissue known as
meninges.
Between the meninges and the central
nervous system tissue is a space filled
with cerebrospinal fluid.
Cerebrospinal fluid acts as a shock
absorber that protects the central nervous
system.
Cerebrospinal fluid also permits exchange
of nutrients and waste products between
blood and nervous tissue.
Bell Ringer
Mrs. Albertson, a new mother, brings her infant to
the clinic because he has suffered repeated seizures.
Upon questioning, she states that her labor was
unusually long and difficult. What might be the
problem?
Central Nervous System
Objective
1) Identify and label major structures and
functions of the brain as seen from the lateral
view of a hemisphere.
Agenda
Lesson: Neurotransmitters and the Brain
Activity: Brain Cap
Closure: Q&A
The transmission of an impulse is an
electrochemical event. While the transmission of
the nerve impulse down the neuron is electrical, this
electric charge cannot cross the synaptic space
between neurons.
Instead the electrical signal in the
neuron triggers the vesicles
containing neurotransmitters to
fuse with the axonal terminal. The
neurotransmitters are then released
into the synaptic space. If enough
of the neurotransmitters are released
it will cause the next neuron to begin
the process of generating another
electrochemical nerve impulse.
The Brain
a. The brain is the place to which
impulses flow and from which
impulses originate.
Parts of The Human Brain FIGURE 35-9
Cerebrum
Thalamus
Pineal gland
Hypothalamus
Pituitary gland
Cerebellum
Pons
Brain stem
Medulla
oblongata
Spinal cord
The Cerebrum
a. The largest and most prominent
region of the human brain is the
cerebrum.
b. It controls
the voluntary, or
conscious, activities of the
body.
c. It is the site of intelligence, learning,
and judgment.
A deep groove divides the cerebrum into
hemispheres, which are connected by a
band of tissue called the corpus callosum.
Each hemisphere is divided into regions
called lobes.
Lobes of the Cerebrum
FPOT
Friendly
People
Over
There
Somatic sensory area
Primary motor area
Gustatory area
Premotor area
Speech/language area
Frontal
Association Area
General
Interpretation Area
Auditory Area
Broca’s Area
Language
comprehension
Olfactory Area
Visual area
Each half of the cerebrum deals with the
opposite side of the body:
a. The left half of the cerebrum
controls the right side of the body.
b. The right half of the cerebrum
controls the left side of the body.
The Cerebellum
a. The second largest region of the
brain is the cerebellum.
b.It coordinates and balances
the actions of the muscles so
that the body can move gracefully
and efficiently.
Check knowledge
A
B
D
C
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Brain Cap Project
Due on the day of the mid-term exam.
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The outer layer of the cerebrum is called
the cerebral cortex and consists of gray
matter.
The inner layer of the cerebrum consists of
white matter, which is made up of bundles
of axons with myelin sheaths.
Cerebellum
The Brain Stem
a. The brain stem connects the brain and
spinal cord.
b. It has two regions: the
pons and the
medulla oblongata regulate
information flow between the
brain and the rest of the body.
c.Blood pressure, heart rate,
breathing, and swallowing are
controlled in the brain stem.
Pons
Brain stem
Medulla oblongata
The Thalamus and Hypothalamus
a. The thalamus receives messages
from all sensory receptors
throughout the body and relays the
information to the proper region of
the cerebrum for further processing.
a.The hypothalamus controls
recognition and analysis of
hunger, thirst, fatigue, anger,
and body temperature.
b. It controls coordination of the
nervous and endocrine systems.
Thalamus
Hypothalamus
Bell Ringer
Name the four lobes of the cerebrum and
explain one function found in each of them.
(note: You can refer to your brain cap project
sheet if needed) Write in complete sentences.
Have one person from your group pick up your
folders.
Central Nervous System
Objective
1) Identify and label major structures of the
spinal cord.
Agenda
Lesson: Spinal Cord Structure
Activity: Spinal Cord Diagram
Closure: Q&A
The Spinal Cord
a. The spinal cord is the main
communications link between the
brain and the rest of the body.
b. Certain information, including
some kinds of reflexes, are
processed directly in the
spinal cord.
c. A reflex is a quick, automatic
response to a stimulus.
The Spinal Cord Structure
•
Spinal Cord
A.
B.
Two Enlargements
1)
Cervical enlargement
2)
Lumbar enlargement
31 Segments in four areas
1)
C1 – C8 = Cervical Segments
2)
T1 – T12 = Thoracic Segments
3)
L1 – L5 = Lumbar Segments
4)
S1 – S5 = Sacral Segments
Bell Ringer
A 75-year-old woman and her 9-year old
granddaughter were in a train crash in which
both sustained trauma to the spine. The
grandmother is not able to move her legs and
x-rays show that she has several fractured
vertebrae. Other than some bruising and cuts,
her granddaughter can move around normally
and the x-rays show no breaks or fractures.
Explain these surprisingly different
findings.
Central Nervous System
Objective
1) Identify and label major structures of the
spinal cord.
Agenda
Lesson: Spinal Cord Structure
Activity: Spinal Cord Diagram
Closure: Q&A
The Spinal Cord Structure
Spinal Cord ends after L1 by splitting
into spinal nerves (lumbar spinal
nerves, sacral spinal nerves, and
coccygeal spinal nerves.
A.
Cauda Equina (horse tail)
1)
Begins at L2 after lumbar enlargement
2)
Made up of two parts
a)
Conus medullaris
b)
Filum terminal
5th
&7th
1.
2.
3.
4.
Title color (your choice - light)
Colors for a- e (your choice)
Spinal cord A – (Your choice)
AC, AT, AL, and AS with
nerve associated nerves –
(Colors related to spinal cord A)
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1.
2.
3.
4.
A – Spinal Cord
Color enlargement arrows
Color nerve segments.
Color cauda equina
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How many segments total?
A) 1
B) 12
C) 31
D) 62
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The 1st through 8th segment area is known
as…
A) Cervical
B) Lumbar
C) Sacral
D) Thoracic
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Which segment is technically NOT part of
the spinal cord?
A) Cervical
B) Lumbar
C) Sacral
D) Thoracic
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The englarged area of the spine where
nerves exit to reach the arms….
A) Cervical
B) Lumbar
C) Sacral
D) Thoracic
Copyright Pearson Prentice Hall
1. Color the title (light)
2. Color a- e (your choice)
3. Pick color for the spinal cord
and 5 related colors for the
spinal cord sections AC, AT,
AL, and AS with nerve
associated nerves.
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Bell Ringer
Based on what you have
learned about the structure of
the spinal cord, which
segment would be the safest
area to insert a needle to
remove cerebral spinal fluid?
(cervical, thoracic, or lumbar).
Explain your reasoning.
Hint: Refer to your spinal cord diagram
handout and notes.
Grades
Brain notes?
Spinal Cord notes
Spinal Cord diagram
Brain cap project
Turn in folders at end of class.
Central Nervous System
Objective
1) Describe the methods of testing for CNS
problems.
Agenda
Lesson: Cerebral Spinal Fluid and Testing the CNS
Group Reading Activity: Tracking Down CNS Problems
Closure: Q&A
Lumbar Puncture
• Performed at L3/L4 or L4/L5
• May remove fluid for testing or inject
medications.
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Epidural during pregnancy – Used to
administer a shot or a continuous
flow of anesthesia through a catheter.
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Needle and catheter
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Activity – Procedures for testing for
problems with the CNS.
Read handout “Tracking Down CNS
Problems”
Complete chart (Divide among group
members and combine)
CNS Testing Procedures
Test
MRI Scans
•Electroencephalogram
•Pneumoencephalography
•Cerebral angiogram
•PET Scans
Description & purpose
Magnetic Resonance Imagining
– Uses magnetic fields to cause
hydrogen molecules in the water
of soft tissues to spin and show
up on images. Shows CSF and
blood flow in the brain that
cannot be seen in x-rays. Can
identify blockages and tumors.
Bell Ringer
A three year old is brought to the emergency
room by his mother. She states that he had a
seizure an hour ago. Triage results show the
child to have a temperature of 102º F (38.9º C).
Stiff neck when bending, and lethargic. What
do you think may be the problem and what
test(s) would you order?
Explain your reasoning.
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1. Color the title (light)
2. Color a- e (your choice)
3. Pick color for the spinal cord
and 5 related colors for the
spinal cord sections AC, AT,
AL, and AS with nerve
associated nerves.
Copyright Pearson Prentice Hall
Which segment is technically NOT part of
the spinal cord? Explain why your answer
is the best and the others are not correct.
A) Cervical
B) Lumbar
C) Sacral
D) Thoracic
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Central Nervous System
Objective
Identify the structures of the gray matter
of the spinal cord and the spinal roots.
Agenda
Lesson: Spinal cord gray matter and roots
Activity: Spinal Cord Diagram
Closure: Q&A
Remember to explain why your answer is more
correct than the others. Three sentence minimum.
How many spinal segments total?
A) 1
B) 12
C) 31
D) 62
Copyright Pearson Prentice Hall
Central Nervous System
Objective
1) Locate the key anatomical structures of the spinal cord,
and spinal nerves.
2) Describe the results of homeostatic imbalance of the
spinal cord and spinal nerves.
Agenda
Lesson: Spinal cord and spinal nerve anatomy &
homeostatic imbalance
Activity: Pair/share practice locating structures
Closure: Q&A
Reminder
Leave your folders at the end of class.
Spinal Cord
Gray Matter (H
shape)– Surrounds the
central canal. Contains
neurons associated
with the spinal nerves.
White matter –
Surrounds the gray
matter. Contains
sensory and motor
nerve impulses to and
from the brain.
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Spinal Nerves
Located in pairs at
each vertebrae.
Dorsal root and
dorsal ganglion are
located in the back.
They are associated
with the dorsal areas of
the gray matter and are
responsible for
transmitting sensory
impulses.
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Spinal Nerves
Ventral roots are
located in the front.
They are associated
with voluntary motor
nerve impulses.
Ventral and dorsal
roots fuse to form the
spinal nerves.
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Homeostatic Imbalance
Dorsal Root/Ganglion Damage
• What would be the impact on
the patient?
•Loss of sensory sensation in the
body area served.
So…. Why
does only
ventral root
damage cause
muscles to
atrophy?
Ventral Root Damage
•What would be the impact on
the patient?
• Flaccid paralysis of associated
muscles
Copyright Pearson Prentice Hall
Central Nervous System
Objective
1) Locate the key anatomical structures of the spinal cord,
and spinal nerves.
2) Describe the results of homeostatic imbalance of the
spinal cord and spinal nerves.
Agenda
Lesson: Spinal cord and spinal nerve anatomy &
homeostatic imbalance
Activity: Pair/share practice locating structures
Closure: Q&A
P
A
D
Pair/Share
Cover up the key on your
colored diagram. Pair up and
quiz each other on the: gray
matter, white matter, dorsal
root, ventral root, dorsal root
ganglion, and spinal nerve.
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Knowledge Check
Which letter of the alphabet best
describes the gray matter of the
spinal cord?
A. H
B. M
C. S
D. T
Knowledge Check
A patient has lost voluntary movement of
their right arm and the muscles have
begun to atrophy in that arm. Which area
of the spinal cord may be damaged?
A.
B.
C.
D.
E.
Dorsal ganglion
Dorsal root
Ventral ganglion
Ventral root
A&B
Knowledge Check
The outer most covering (meninges) of
the spinal cord.
A.
B.
C.
D.
Arachnoid mater
Dura mater
Pia mater
Gray mater
Knowledge Check
A patient is able to use their legs but
complains of numbness. What part of the
spinal cord may be damaged?
A.
B.
C.
D.
E.
Dorsal ganglion
Dorsal root
Ventral ganglion
Ventral root
A&B
Remember
to justify
your
answer. 3
sentence
minimum
After this touchdown the player complained of numbness
and tingling in his right hand. Which part of the spinal
nerve would you suspect is the problem?
A) Dorsal root B) Ventral Root
C) Lateral Root D) Superior root
Remember to justify your answer. 3 sentence minimum
What is the correct order of the meninges from
the membrane that is most proximal to the spinal
cord to the membrane that is more superficial.
A)
B)
C)
D)
Arachnoid, Dura, Pia
Dura, Pia, Arachnoid
Pia, Dura, Arachnoid
Pia, Arachnoid, Dura
Remember to justify your answer. 3 sentence minimum
What is the correct order of the meninges from
the membrane that is most proximal to the spinal
cord to the membrane that is more superficial.
A)
B)
C)
D)
Arachnoid, Dura, Pia
Dura, Pia, Arachnoid
Pia, Dura, Arachnoid
Pia, Arachnoid, Dura
3 sentence minimum
Describe any one of our reflexes. How does this
reflex help us?
Central Nervous System
Objective
1)Review material for the nervous system
Agenda
Lesson: Review of central nervous system.
TEST WILL BE FRIDAY
Activity: Standard Deviants Nervous System Video
Closure: Q&A
Central Nervous System
Objective
1)Review material for the nervous system
Agenda
Lesson: Review of central nervous system.
TEST WILL BE FRIDAY
Activity: Standard Deviants Nervous System Video
Closure: Q&A
Video Questions
1. What is the difference between the CNS and the
PNS?
2. Describe the 4 major parts of the brain:
•Cerebrum
•Diencephalon
•Brain Stem
•Cerebellum
3. What are 3 things that protect the brain?
4. What is the difference between a concussion and
a contusion of the brain?
5. What are the two major degenerative brain
disorders? –
Extra video
Reminder
Leave your folders at the end of class.
Knowledge Check
A patient in the ER has a gunshot wound to
the lumbar region. He states he cannot feel
or move his legs. An MRI shows a
laceration of the outermost layer of the
meninges but the spinal cord is intact.
What is the name of this meninges and why
might damage to this layer be causing the
patient’s symptoms? What do you think
should be done? Do you believe the
symptoms are permanent or is there a
possibility they are temporary?
Bell Ringer
A patient arrives in the ER. They complain
that they slipped on some ice and hit their
head. They felt fine at first but when they
woke up this morning they were unable to
see. What do you think might be possibly
causing the problem? Explain your answer.
Bell Ringer
The day after their baby is born, the parents
are told that their daughter was born with an
enlarged head and that in the last 24 hours
it has increased in size. The doctor tells
them that condition is called hydrocephalus
or “water on the brain”. What do you think
is happening with the baby and why might it
be dangerous? What do you think can be
done to help the baby?
Nervous System
Objective
1)Determine how reaction times change over time
with practice.
Agenda
Lesson: Reflexes and reactions
Activity: Complete Lab activity – Reflexes and
reactions
Closure: Q&A
Reminder
Leave your folders at the end of class.
Review Reflexes
A reflex, is an involuntary and
nearly instantaneous movement
in response to a stimulus.
Examples:
Pupillary reflex
Blink reflex
Knee Jerk reflex
Gag reflex
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Voluntary Reaction Testing
With your partners:
Perform the stick drop reaction
test.
Record 5 times
How did it change over time?
Why would a voluntary reaction
take longer than a simple reflex?
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Extended Investigation
With the same test subject:
Have them run in place for 5
minutes.
Re-test their reaction time with
the ruler drop test.
Other than exercise, what might
change a person’s reaction
time?
Copyright Pearson Prentice Hall
Exit Ticket
On the bottom of your activity sheet,
answer the following:
•
Why are voluntary reaction
times slower than simple
reflex reactions?
Place your activity sheet in the
back pocket and leave your
folders in the class box.
Knowledge Check
A patient has lost voluntary movement of
their right arm and the muscles have
begun to atrophy in that arm. Which area
of the spinal cord may be damaged?
A.
B.
C.
D.
E.
Dorsal ganglion
Dorsal root
Ventral ganglion
Ventral root
A&B
Knowledge Check
What is the correct order of the meninges
from inner most to outer most mater
layers.
A.
B.
C.
D.
Arachnoid, Dura, Pia
Dura, Arachnoid, Pia
Pia, Arachnoid, Dura
Pia, Dura, Arachnoid
Knowledge Check
Which of the following is the “hard
mother
A.
B.
C.
D.
Arachnoid mater
Dura mater
Pia mater
Gray mater
Knowledge Check
Which letter of the alphabet best
describes the gray matter of the
spinal cord?
A. H
B. M
C. S
D. T
Reminder
Leave your folders at the end of class.
P
A
D
Pia Mater (Gentle Mother)
Membrane that clings tightly to the surface of the
brain and the spinal cord. It is impermeable to fluids
but allows blood vessels to pass through.
H.I. – When inflamed it is called meningitis.
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P
A
D
Arachnoid Mater (Spider mother)
Lies between the pia mater and the dura mater.
Cerebral spinal fluid can flow through this membrane.
The subarachnoid space (between the pia and the
arachnoid) is where the needle for lumbar punctures is
inserted to remove CSF.
P
A
D
Dura Mater (Hard mother)
The outer most layer. It is responsible for keeping
the CSF between it and the pia mater.
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Cerebrospinal Fluid (CSF)
•Similar to blood
plasma.
•Permits exchange of
nutrients and waste
products between
blood and nervous
tissue.
MRI of CSF
5
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Cerebrospinal Fluid
(CSF)
•Surrounds and
cushions the brain
and spinal cord.
•Produced from
blood in two areas
in the brain called
the choroid plexus.
Pair/Share
Cover up the key on your colored
diagram. Pair up and quiz each
other on the structures shown
above. Describe them as well.
Copyright Pearson Prentice Hall
Copyright Pearson Prentice Hall
Vocabulary Card Activity
Instructions:
• Draw a picture with a pen or pencil that will
help you remember the meaning and/or
location of the term. The drawing should be
large.
• Cut out the cards.
• On the back write the meaning of the term or
location/role o the structure in your own words
(use notes and/or coloring diagrams).
• Use extra time to color in your drawing.
Copyright Pearson Prentice Hall
Frontal Lobe
Copyright Pearson Prentice Hall
Reminder
Leave your folders at the end of class.
Knowledge Check
What is the correct order of the meninges
from inner most to outer most mater
layers.
A.
B.
C.
D.
Arachnoid, Dura, Pia
Dura, Arachnoid, Pia
Pia, Arachnoid, Dura
Pia, Dura, Arachnoid
Knowledge Check
Which of the following is the “hard
mother
A.
B.
C.
D.
Arachnoid mater
Dura mater
Pia mater
Gray mater
Knowledge Check
A patient has lost voluntary movement of
their right arm and the muscles have
begun to atrophy in that arm. Which area
of the spinal cord may be damaged?
A.
B.
C.
D.
E.
Dorsal ganglion
Dorsal root
Ventral ganglion
Ventral root
A&B
Knowledge Check
Which letter of the alphabet best
describes the gray matter of the spinal
cord?
A.
B.
C.
D.
H
M
S
T
WAC
Sit quietly for a moment. Focus on the
physical sensations you are having.
What temperatures do you feel?
Pressure? Pain? Any other sensations?
Describe in 3 or more sentences.
Peripheral Nervous System
Objective
1)Describe the divisions of the peripheral nervous
system
2)Differentiate between the somatic nervous system and
the autonomic nervous system.
3)Describe a reflex arc.
Agenda
Lesson: Peripheral Nervous System – motor division
(somatic and autonomic).
Activity – Standard Deviants
The Peripheral Nervous System
a.The peripheral nervous system is
all of the nerves and associated
cells that are not part of the brain
and the spinal cord.
b. The peripheral nervous system includes
cranial nerves, spinal nerves, and ganglia.
c. Ganglia are collections of nerve cell
bodies.
Peripheral Nervous System has 2 main
divisions:
•The sensory division
•Impulses from sense organs to CNS
•The motor division
•Impulses from the CNS to the muscles
and glands
Knowledge Check:
•Which of the following regulates impulses
traveling from the CNS to the muscles and
glands?
A. Motor Division
B. Sensory Division
C. Autonomic Nervous System
D. Somatic Nervous System
The motor division is divided into 2
systems: somatic and the autonomic
nervous systems.
Knowledge Check:
•Which part of the motor division handles
things that involve conscious control?
A. Motor Division
B. Sensory Division
C. Autonomic Nervous System
D. Somatic Nervous System
Somatic nervous system
•regulates activities that are under conscious
control, such as the movement of skeletal
muscles.
-
The Somatic Nervous System
a.Some somatic nerves are
involved with reflexes = react to
pain.
Sensory neuron
a. Reflex Arc
Motor
neuron
Interneuron
Spinal cord
Effector (responding
muscle)
Sensory
receptors
A reflex arc includes:
• a sensory receptor
• sensory neuron
• motor neuron, and
• an effector (responding muscle)
Knowledge Check:
•The peripheral nervous system is made
up of the following 2 divisions:
A. Autonomic and somatic
B. Motor and sensory
C. Peripheral and central
D. Spinal nerves and cranial nerves
Knowledge Check:
•Which of the following regulates impulses
traveling from the sensory receptors to the
CNS:
A. Motor
B. Sensory
C. Autonomic
D. Somatic
Knowledge Check:
•Which of the following regulates impulses
traveling from the CNS to the muscles and
glands?
A. Motor Division
B. Sensory Division
C. Autonomic Nervous System
D. Somatic Nervous System
Knowledge Check:
•Which part of the motor division handles
things that involve conscious control?
A. Motor Division
B. Sensory Division
C. Autonomic Nervous System
D. Somatic Nervous System
WAC
After a baby wellness check, you are told that your
child has a condition called "congenital insensitivity
to pain". Her nervous systems is not equipped to
detect painful information.
How might this cause problems as your child grows
and develops? What precautions might you need to
take?
Peripheral Nervous System
Objective
1)List and describe the types of sensory receptors
Agenda
Lesson: Sensory Receptors
Activity – Word Wall Signs
Neurons that react directly to stimuli from
the environment are called sensory
receptors.
Sensory receptors react to stimuli
by sending impulses to other
neurons and to the central
nervous system.
Sensory receptors are located throughout
the body but are concentrated in the sense
organs.
5 categories of sensory receptors:
a.pain receptors
b.Thermoreceptors- heat
c.Mechanoreceptors- pressure
d.Chemoreceptors- chemicals
NOSE & TASTE BUDS
e.Photoreceptors- light
EYES
Pain receptors are located throughout the
body except in the brain.
They respond to chemicals released by
damaged cells.
Pain usually indicates danger, injury, or
disease.
Thermoreceptors are located in the skin,
body core, and hypothalamus.
They detect variations in temperature.
Mechanoreceptors are found in the skin,
skeletal muscles, and inner ears.
They are sensitive to touch, pressure,
stretching of muscles, sound, and motion.
Chemoreceptors, located in the nose and
taste buds, are sensitive to chemicals in
the external environment.
Photoreceptors, found in the eyes, are
sensitive to light.
WAC
Tactile fremitus is a vibration of the human body that
can be felt by placing a hand in the area where the
vibration is occurring. For instance, when you place
a hand on a patient’s back and feel a vibration when
they breath, it may indicate fluid in the lungs.
Which sensory receptors in the hand do you think
are detecting this vibration?
A. Thermoreceptors
Explain how you
B. Pain receptors
C. Photoreceptors
eliminated at least one of
D. Mechanoreceptors the answers. 3 SENTENCES.
Peripheral Nervous System
Objective
1)Differentiate between the sympathetic and
parasympathetic divisions of the autonomic nervous
system.
Agenda
Lesson: Sensory Receptors
Activity – Word Wall Signs
The autonomic - regulates involuntary
activities.
The Autonomic Nervous System
The autonomic nervous system is
subdivided into two parts:
1.sympathetic
2.parasympathetic
Nervous
System
Central
Brain
Spinal Cord
Peripheral
Sensory
Motor
Somatic
Autonomic
Sympathetic
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Parasympathetic
The sympathetic and parasympathetic
nervous systems have opposite effects on
the same organ system.
These opposing effects help maintain
homeostasis.
Simplified Rule of Thumb:
•Sympathetic – Fight or Flight
•Parasympathetic – Rest and Digest
Sympathetic – Regulates the organs under
stress conditions.
Organ
Effect
Eye
Dilates pupil
Heart
Increases rate and force of
contraction
Lungs
Dilates bronchioles
Blood Vessels
Constricts
Sweat Glands
Activates sweat secretion
Digestive tract
Inhibits peristalsis
Kidney
Increases renin secretion
Penis
Promotes ejaculation
Sympathetic – Made up of pre-ganglionic and
post-ganglionc nerves.
Pre-ganglionic – releases acetylcholine
(ACh) that stimulates the post-ganglionic nerves.
Post-ganglion – releases noradrenaline
(also called norepinephrine) which excites some
organs and inhibits others.
Parasympathetic – Regulates the organs under
restful conditions for maintenance.
Organ
Effect
Eye
Constricts pupil
Heart
Lowers rate and force of
contraction
Respiratory
Constricts bronchioles &
stops nasal secretions
Blood Vessels
Dilate – lowers BP
Digestive tract
Stimulates digestion
Excretory
Contracts bladder; decrease
fluid retention
Penis
Sexual arousal
WAC
Which division of the autonomic system handles
bodily functions when under stress?
A.
B.
C.
D.
somatic
sympathetic
Parasympathetic
Pre-ganglionic
WAC
Under the parasympathetic system the digestive
system is
A.
B.
C.
D.
inhibited
increased
unaffected
infected
WAC
Under the parasympathetic system the pupils
A.
B.
C.
D.
dilate
constrict
become watery
blink
WAC
Under the sympathetic system the heat beat and
blood pressure
A.
B.
C.
D.
decrease
increase
dilate
stop
WAC
Under the sympathetic system the bronchioles
A.
B.
C.
D.
decrease
are inhibited
dilate
constrict
WAC
Under the autonomic system the post-ganglionic
nerves release this neurotransmitter which inhibits
some organs and excites others
A.
B.
C.
D.
noradrenalin
Acetylcohline
dilantin
epinephrin
WAC
Explain in your own words the key differences
between the sympathetic and parasympathetic
nervous systems. Give at least two examples of
how organs react differently to these systems.
OBJECTIVES:
•Identify the 3 major parts of the eye.
•Differentiate between the three tunics of the
eye.
AGENDA
> Detecting the blind spot
activity
>Standard Deviants Video
Clip (3 min)
> Notes on the eye
Sense organs include the:
a. Eyes (Contain over 70% of all
sensory receptors)
b.ears
c. nose
d.mouth
e. skin
Standard Deviants Video of Eye Anatomy
Click and go to 15:48 of the video
3 main parts of the eye:
Humors (fluids)
Tunics (layers)
Lens
Vision
a. The sense organ that animals use to
sense light is the eye.
b. The eye has three layers called
tunics:
1.
Fibrous tunic (avascular)
a) Sclera & Cornea
2.
Vascular tunic (middle layer)
a) Choroid
b) Ciliary body
c) Iris
Vision
b. The eye has three layers called
tunics: (continued)
3.
Sensory Tunic (Retina)
• Pigmented and neural
layers
WAC
If you had to lose one of your 5
senses, which would you choose
and why?
WAC
Under the autonomic system the post-ganglionic
nerves release this neurotransmitter which inhibits
some organs and excites others
A.
B.
C.
D.
noradrenalin
Acetylcohline
dilantin
epinephrin
Explain how you
eliminated at least one
of your answers.
OBJECTIVES:
•Identify the 3 major parts of the eye.
•Differentiate between the three tunics of the
eye.
AGENDA
> Notes on the tunics of
the eye.
> Complete eye diagram
and begin ear diagram.
WAC
Which division of the autonomic system handles
bodily functions when under stress?
A.
B.
C.
D.
somatic
sympathetic
Parasympathetic
Pre-ganglionic
WAC
Under the parasympathetic system the digestive
system is
A.
B.
C.
D.
inhibited
increased
unaffected
infected
WAC
Under the parasympathetic system the pupils
A.
B.
C.
D.
dilate
constrict
become watery
blink
WAC
Under the sympathetic system the heat beat and
blood pressure
A.
B.
C.
D.
decrease
increase
dilate
stop
WAC
Under the sympathetic system the bronchioles
A.
B.
C.
D.
decrease
are inhibited
dilate
constrict
WAC
Under the autonomic system the post-ganglionic
nerves release this neurotransmitter which inhibits
some organs and excites others
A.
B.
C.
D.
noradrenalin
Acetylcohline
dilantin
epinephrin
FIBROUS TUNIC
The sclera is the outer layer of eye that
maintains its shape.
The sclera serves as point of attachment
for muscles that move the eye.
Sclera
FIBROUS TUNIC
Light enters the eye through the cornea,
a tough transparent layer of cells.
Cornea
FIBROUS TUNIC
The cornea helps focus light, which
then passes through a chamber filled
with a fluid called aqueous humor.
Aqueous
humor
Cornea
VASCULAR TUNIC
The choroid is the middle layer of eye that
is rich in blood vessels.
Choroid
VASCULAR TUNIC
At the back of the chamber is a disklike
structure called the iris, which is the
colored part of the eye.
Iris
In the middle of the iris is a small opening
called the pupil. Muscles in the iris adjust
pupil size to regulate the amount of light
that enters the eye.
Pupil
In dim light, the pupil becomes larger.
(dilates)
In bright light, the pupil becomes
smaller. (constricts)
SENSORY TUNIC
The retina is the inner layer of
eye that contains
photoreceptors.
Retina
Just behind the iris is the lens.
Muscles attached to the lens change its
shape to adjust focus to see near or
distant objects.
Lens
Behind the lens is a large chamber filled
with a transparent, jellylike fluid called
vitreous humor.
Vitreous humor
Test Wed.
on
Peripheral
& Eye
Bell Ringer
Match each sensory receptor to the type of stimulus
to which it is likely to respond.
1.
2.
3.
4.
5.
Chemoreceptor
Pain receptor
Thermoreceptor
Mechanoreceptor
Photoreceptor
A.
B.
C.
D.
E.
Approaching headlights
Soft sheets
The smell of roses
An infected tooth
A cool breeze
Explain how you matched up at least two of
them.  - 3 Sentence Minimum.
OBJECTIVES:
•Describe the role of the retina and 5 conditions
which can cause problems.
•Differentiate between rods and cones.
AGENDA
> 2 minute video clip on
how light travels through
the eye.
> Notes on the retina.
> Finish eye and ear
diagrams.
The lens focuses light onto the
retina.
Photoreceptors are arranged in a layer in
the retina.
Retina
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Macular
Degeneration
Copyright Pearson Prentice Hall
Glaucoma
Fig. 23. A view of the fundus of the eye and of the retina
Copyright
Pearson
Prentice Hall
in a patient who
has
advanced
glaucoma.
Retinitis pigmentosa
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Diabetic retinopathy
Copyright Pearson Prentice Hall
Rods and cones are photoreceptors.
•Rods are sensitive to light but not color.
•Cones are sensitive to light of different colors
and produce color vision.
Cones are concentrated in the fovea, which
is the site of sharpest vision.
Fovea
The impulses travel from each eye to the
brain by way of the optic nerve where they
are interpreted as visual images.
Optic nerve
The impulses travel from each eye to the
brain by way of the optic nerve where they
are interpreted as visual images.
Optic nerve
Bell Ringer
Test Wed.
on
Peripheral
& Eye
You take a sip of soup. It is hot and burns your
mouth. What receptors were involved in this
experience? Write in complete sentences (3
minimum) explaining your choices.
OBJECTIVES:
•Practice questions on the peripheral nervous
system and the eye.
•Notes – external anatomy of the ear.
AGENDA
> Practice questions
> Notes on the ear.
> Practice questions.
Nervous
System
Central
Brain
Spinal Cord
Peripheral
Sensory
Motor
Somatic
Autonomic
Sympathetic
Copyright Pearson Prentice Hall
Parasympathetic
Knowledge Check:
•Sensory receptors are found
concentrated in the nose and on the
tongue:
A. Pain receptors
B. Chemoreceptors
C. Mechanoreceptors
D. Thermoreceptors
Knowledge Check:
•The sensation of a cool breeze against the
skin would be detected by what receptors
A. Pain receptors and mechanoreceptors
B. Chemoreceptors and thermoreceptors
C. Mechanoreceptors and thermoreceptors
D. Thermoreceptors and pain receptors
Knowledge Check:
•The nervous system is divided into two
major systems:
A. Autonomic and somatic
B. Motor and sensory
C. Spinal nerves and cranial nerves
D. Peripheral and central
Knowledge Check:
•The central nervous system is made up
of:
A. Autonomic and somatic nervous
systems
B. Motor and sensory divisions
C. Brain and spinal cord
D. Spinal nerves and cranial nerves
Knowledge Check:
•The peripheral nervous system is made
up of the following 2 divisions:
A. Autonomic and somatic
B. Motor and sensory
C. Peripheral and central
D. Spinal nerves and cranial nerves
Knowledge Check:
•Which of the following regulates impulses
traveling from the sensory receptors to the
CNS:
A. Motor
B. Sensory
C. Autonomic
D. Somatic
Knowledge Check:
•Which of the following regulates impulses
traveling from the CNS to the muscles and
glands?
A. Motor Division
B. Sensory Division
C. Autonomic Nervous System
D. Somatic Nervous System
Knowledge Check:
•Which part of the motor division handles
things that involve conscious control?
A. Motor Division
B. Sensory Division
C. Autonomic Nervous System
D. Somatic Nervous System
Which division of the autonomic system handles
bodily functions when under stress?
A.
B.
C.
D.
somatic
sympathetic
Parasympathetic
Pre-ganglionic
Under the parasympathetic system the digestive
system is
A.
B.
C.
D.
inhibited
increased
unaffected
infected
Under the parasympathetic system the pupils
A.
B.
C.
D.
dilate
constrict
become watery
blink
Under the sympathetic system the heat beat and
blood pressure
A.
B.
C.
D.
decrease
increase
dilate
stop
Under the sympathetic system the bronchioles
A.
B.
C.
D.
decrease
are inhibited
dilate
constrict
Under the autonomic system the post-ganglionic
nerves release this neurotransmitter which inhibits
some organs and excites others
A.
B.
C.
D.
noradrenalin
Acetylcohline
dilantin
epinephrin
Divisi
ons of
the
Ear
Peripheral Mechanism
VIII
Outer Middle Inner
Cranial
Ear
Ear
Ear
Nerve
Central
Mechanism
Brain
Questi
on
What is the purpose of the pinna?
A. Cosmetics
B. Sound collector
C. Same side localization
D. A and B
E. A, B and C
Senteo Question
To set the properties right click and select
Senteo Question Object->Properties...
Outer
Ear
Virtual Tour of the
Ear
Pinna
Pinna
Preauricular Tags
Preauricular Pits
External
Auditory
Meatus
EAM
Q-tips
Function
Cerumen
Microtia EAM
resonance
Anotia
Pinna
Another name for pinna?
A. External auditory meatus
B. External auditory canal
C. Ear lobe
D. Auricle
E. None of the above
Senteo Question
To set the properties right click and select
Senteo Question Object->Properties...
on of
Outer
Ear
Collect sound
Localization
Resonator
Protection
Sensitive
(earlobe)
Other?
Pinna
The visible portion that is
commonly referred to as
"the ear"
Helps localize sound
sources
Directs sound into the ear
Each individual's pinna
creates a distinctive
imprint on the acoustic
wave traveling into the
auditory canal
Audit
ory
Meatu
s
Extends from the pinna to the tympanic membrane
About 26 millimeters (mm) in length and 7 mm in diameter in
adult ear.
Size and shape vary among individuals.
Protects the eardrum
Resonator
Provides about 10 decibels (dB) of gain to the eardrum at
around 3,300 Hertz (Hz).
The net effect of the head, pinna, and ear canal is
that sounds in the 2,000 to 4,000 Hz region are
amplified by 10 to 15 dB.
Sensitivity to sounds greatest in this frequency region
Outer Ear Resonance
Influence of pinna
(p)
Influence of ear
canal (m)
Combine influence
(t)
At 3000 Hz, the final
amplification (t) is 20
dB
Cerumen should be routinely removed
from the ear canal?
A. True
B. False
Senteo Question
To set the properties right click and select
Senteo Question Object->Properties...
Cerum
en
The purpose of wax:
Repel water
Trap dust, sand particles,
micro-organisms, and other
debris
Moisturize epithelium in ear
canal
Odor discourages insects
Antibiotic, antiviral, antifungal
al
Devel
opme
nt
External Ear Development
Hearin
g
Disord
ers
Outer ear
CHARGE
Down Syndrome
Ears small and low set
Fetal Alcohol
Syndrome
Deformed ears
DiGeorge syndrome
Low set ears
Extern
al Ear
Care
Hazardous to
health:
Ear candling
Swabs
Foreign objects
The Ear
a.The human ear has two
sensory functions:
hearing
balance
Hearing
a. Ears can distinguish both the pitch
and loudness of those vibrations.
The Human Ear Figure 35-14 pg908
Locate- Tympanum, hammer, anvil, stirrup,
& cochlea
Vibrations enter the ear through the
auditory canal.
Auditory
canal
The vibrations
cause the
tympanum, or eardrum, to vibrate.
Tympanum
The vibrations are picked up by the
hammer, anvil, and stirrup.
Hammer
Anvil
Stirrup
The stirrup transmits the
vibrations to the oval window.
Stirrup
Oval window
Vibrations of the oval window
create pressure waves in the fluidfilled cochlea of the inner ear.
Cochlea
The fluid-filled cochlea is lined
with tiny hair cells that are
pushed back and forth by these
pressure waves.
In response to the waves, the
hair cells
produce nerve impulses that are
sent to the brain through the cochlear
nerve.
Balance
a. Your ears help you to maintain your
balance, or equilibrium.
Within the inner ear, just above the
cochlea are three semicircular canals.
Semicircular canals
The canals are filled with fluid and lined
with hair cells.
As the head changes position, fluid in the
canals changes position, causing the hair
on the hair cells to bend.
This sends impulses to the brain that
enable it to determine body motion and
position.
Smell
a. The sense of smell is actually an
ability to detect chemicals.
b. Chemoreceptors in the nasal
passageway respond to chemicals
and send impulses to the brain
through sensory nerves.
Taste
a. The sense of taste is also a chemical
sense.
b. The sense organs that detect taste
are the taste buds. Most taste buds
are on the tongue.
c. Tastes detected by the taste buds
are classified as salty, bitter, sweet,
and sour.
d. Sensitivity to these tastes varies on
different parts of the tongue.
Touch and Related Senses
a. The skin’s sensory receptors
respond to temperature, touch, and
pain.
b. Not all parts of the body are equally
sensitive to touch, because not all
parts have the same number of
receptors.
c. The greatest density of sensory
receptors is found on your fingers,
toes, and face.
35–5 Drugs and the Nervous
System
A drug is any substance, other than food,
that changes the structure or function of
the body.
Some drugs, such as cocaine and heroin
are illegal. Other drugs, such as penicillin
and codeine are prescribed by doctors.
Still other drugs, including cough
medicines can be purchased over the
counter.
All drugs can be harmful if used
improperly or abused.
Drugs differ in the ways in which they
affect the body.
a. Some kill bacteria and are useful in
treating disease.
b. Others affect a particular system of
the body.
c. Others cause changes to the brain
and synapses.
Stimulants
Stimulants increase heart rate, blood
pressure, and breathing rate. In addition,
stimulants increase the release of
neurotransmitters at some synapses in the
brain.
Common stimulants include amphetamines,
cocaine, nicotine, and caffeine.
Depressants
a. Depressants slow down heart
rate and breathing rate, lower
blood pressure, relax muscles,
and relieve tension.
b. Barbiturates, tranquilizers, and
alcohol are some examples of
depressants.
Cocaine
a. Cocaine causes the sudden release
in the brain of a neurotransmitter
called dopamine.
b. Cocaine also acts as a powerful
stimulant.
Opiates
a. Opiates mimic endorphins which
normally help to overcome
sensations of pain.
b. Common opiates include
morphine and codeine.
Marijuana
a. The most widely abused illegal drug
is marijuana.
b. Marijuana comes from Cannabis
sativa, a hemp plant.
c. Hashish, or hash, is a potent form of
marijuana.
d. The active ingredient in marijuana is
THC.
Long-term use of marijuana can result in:
a. loss of memory
b. inability to concentrate
c. in males, reduced levels of the
hormone testosterone in males
a. Alcohol is a depressant that slows
down the rate at which the central
nervous system functions.
b. Alcohol slows down reflexes,
disrupts coordination, and impairs
judgment.
Heavy drinking fills the blood with so
much alcohol that the central nervous
system cannot function properly.
People who drink a lot of alcohol usually
cannot walk or talk properly, and they are
not able to safely control an automobile.
Pregnant women who drink alcohol risk
having a child with FAS.
Fetal alcohol syndrome (FAS) is a group of
birth defects caused by the effects of
alcohol on the fetus.
FAS can cause minor to serious brain
damage, heart defects, malformed faces,
delayed growth, and poor motor
development.
Alcohol and Disease
a. People who have become addicted
to alcohol suffer from a disease
called alcoholism.
b. If a person cannot function properly
without satisfying the craving for
alcohol, that person has an alcoholabuse problem.
c. Long-term alcohol use destroys liver
cells.
Drug Abuse
a. Drug abuse is the intentional misuse
of any drug for nonmedical
purposes.
b. Drug abuse can cause psychological
dependence or serious physical
damage to the body.
Uncontrollable dependence on a drug is
called an addiction.
Some drugs cause a strong psychological
dependence, or mental craving.
35–1
The type of tissue that holds organs in
place and binds different parts of the
body together is called
a. muscle tissue.
b. epithelial tissue.
c. connective tissue.
d. skeletal tissue.
35–
1
One major function of the
integumentary system is to
a. help regulate body temperature.
b. cause the body to move.
c. provide a surface for gas exchange.
d. control growth, development, and
metabolism.
35–
1
Which of the following is NOT an
example of feedback inhibition?
a. shivering to warm the body
b. sweating to cool the body
c. nervous tissue receiving messages
d. turning on the heating system of a
house
35–
1
The process by which an organism
keeps internal conditions relatively
constant is called
a. a feedback loop.
b. negative feedback.
c. homeostasis.
d. normal temperature.
Which of the following organ systems
transports oxygen, nutrients, and
hormones to cells?
a. circulatory system
b. muscular system
c. excretory system
d. nervous system
35-2
Neurons that carry impulses from the
brain and spinal cord to the muscles
are
a. interneurons.
b. sensory neurons.
c. resting neurons.
d. motor neurons.
35-2
The part of the neuron that carries
impulses toward the cell body is the
a. axon.
b. myelin sheath.
c. dendrite.
d. nodes.
35-2
The minimum level of a stimulus that is
required to activate a neuron is called
its
a. action potential.
b. resting potential.
c. threshold.
d. synapse.
35-2
Chemicals that are used by a neuron to
transmit impulses are called
a. neurotransmitters.
b. synapses.
c. axons.
d. inhibitors.
35-2
An action potential begins when
a. sodium ions flow into the neuron.
b. potassium ions flow into the neuron.
c. sodium and potassium ions flow
into the neuron.
d. sodium and potassium ions flow out
of the neuron.
35-3
The brain stem functions as
a. a location for memory and learning.
b. the control site responsible for heart rate,
blood pressure, and breathing.
c. the location where all sensory information is
processed and delivered to the cerebrum.
d. an area that recognizes hunger, thirst, and
body temperature.
35-3
The left half of the cerebrum largely controls
a. the left side of the body.
b. both the right and left sides of the body.
c. the right side of the body.
d. the right half of the brain.
35-3
The part of the brain that is responsible for
coordination and balance is the
a. cerebellum.
b. cerebrum.
c. brain stem.
d. thalamus.
35-3
Reflex arcs are actions that are a part of the
peripheral nervous system's
a. sensory division.
b. somatic system.
c. autonomic system.
d. motor division.
35-3
Which of the following is NOT under the control
of the autonomic nervous system?
a. heartbeat
b. digestion
c. walking
d. sweating
35–4
The sensory receptor that detects variations in
body temperature is a
a. chemoreceptor.
b. mechanoreceptor.
c. thermoreceptor.
d. photoreceptor.
35–4
The part of the eye containing tiny muscles that
adjust the size of the pupil is the
a. cornea.
b. iris.
c. lens.
d. retina.
35–4
The part of the ear that produces the nerve
impulses sent to the brain is the
a. tympanum.
b. Eustachian tube.
c. cochlea.
d. oval window.
35–4
The structures in your ears that help maintain
your sense of balance
a. is the auditory canal.
b. is the hammer.
c. is the tympanum.
d. are the semicircular canals.
35–4
Photoreceptors in the eye that are sensitive to
color are
a. rods.
b. cones.
c. rods and cones.
d. the optic nerve.
35–5
35–5
A drug that increases the heart rate and
breathing rate is a
a. depressant.
b. opiate.
c. stimulant.
d. barbiturate.
35–5
A powerful stimulant that increases blood
pressure and heart rate that can lead to a heart
attack is
a. cocaine.
b. opium.
c. marijuana.
d. caffeine.
35–5
Many drugs that affect the brain and behavior do
so because they
a. affect organ systems and those changes are
detected by the brain.
b. interfere with the normal functioning of
neurotransmitters.
c. cause the brain to release endorphins.
d. enter the cell bodies of brain neurons
causing them to behave differently.
35–5
True or False? Medically prescribed drugs
cannot cause addiction.
a. True
b. False
35–5
Alcohol acts on the brain as a
a. general stimulant of the nervous system.
b. general depressant of the nervous system.
c. pain reliever acting in the cerebrum.
d. stimulant of the brain stem and cerebellum.
Neurons are classified according to
the direction in which an impulse
travels.
a. Sensory neurons carry impulses from
the sense organs to the spinal cord and
brain.
b. Motor neurons carry impulses from the
brain and spinal cord to muscles and
glands.
c. Interneurons connect sensory and
motor neurons and carry impulses
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Structures of a Neuron
Nucleus
Dendrites
Axon
terminals
Cell body
Myelin sheath
Nodes
Axon
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End Show
Neu
rons
The largest part of a typical neuron is the
cell body.
It contains the nucleus and much of the
cytoplasm.
Cell body
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Neu
rons
Dendrites extend from the cell body and
carry impulses from the environment
toward the cell body.
Dendrites
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Neu
rons
The axon is the long fiber that carries
impulses away from the cell body.
Axon
terminals
Axon
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Neu
rons
The axon ends in axon terminals.
Axon
terminals
Axon
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Neu
rons
The axon is sometimes surrounded by an
insulating membrane called the myelin
sheath.
There are gaps in the myelin sheath, called
ncmodes, where the membrane is exposed.
Impulses jump from one node to the next.
Myelin sheath
Nodes
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