Section 35-1
Chapter 35 –
The Nervous System
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Section:
Section Outline
Section 35-1
35–1
Human Body Systems
A. Organization of the Body
1. Cells – specialized!
2. Tissues
a. Epithelial
b. Connective
c. Nervous
d. Muscle
3. Organs – made of all 4 tissues!
4. Organ Systems – there are ELEVEN!
B. Maintaining Homeostasis
1. A Nonliving Example
2. In the Body – 37C (98.6F)
a. Hypothermia (under heat)
b. Hyperthermia (over heat)
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Section:
Examples of Feedback Inhibition
Section 35-1
Thermostat senses temperature
change and switches off heating
system
Room temperature increases
Room temperature decreases
Thermostat senses temperature
change and switches on heating
system
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Section:
Figure 35-2 Human Organ Systems Part I
Section 35-1
Nervous System
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Section:
Integumentary System
Skeletal System
Muscular System
Circulatory System
Figure 35-2 Human Organ Systems Part I
Section 35-1
Nervous System
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Section:
Integumentary System
Skeletal System
Muscular System
Circulatory System
Figure 35-2 Human Organ Systems Part I
Section 35-1
Nervous System
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Section:
Integumentary System
Skeletal System
Muscular System
Circulatory System
Figure 35-2 Human Organ Systems Part I
Section 35-1
Nervous System
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Section:
Integumentary System
Skeletal System
Muscular System
Circulatory System
Figure 35-2 Human Organ Systems Part I
Section 35-1
Nervous System
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Section:
Integumentary System
Skeletal System
Muscular System
Circulatory System
Figure 35-2 Human Organ Systems Part 2
Section 35-1
Respiratory System
Endocrine System
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Section:
Digestive System
Reproductive System
Excretory System
Lymphatic/Immune Systems
Figure 35-2 Human Organ Systems Part 2
Section 35-1
Respiratory System
Endocrine System
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Section:
Digestive System
Reproductive System
Excretory System
Lymphatic/Immune Systems
Figure 35-2 Human Organ Systems Part 2
Section 35-1
Respiratory System
Endocrine System
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Section:
Digestive System
Reproductive System
Excretory System
Lymphatic/Immune Systems
Figure 35-2 Human Organ Systems Part 2
Section 35-1
Respiratory System
Endocrine System
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Section:
Digestive System
Reproductive System
Excretory System
Lymphatic/Immune Systems
Figure 35-2 Human Organ Systems Part 2
Section 35-1
Respiratory System
Endocrine System
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Section:
Digestive System
Reproductive System
Excretory System
Lymphatic/Immune Systems
Figure 35-2 Human Organ Systems Part 2
Section 35-1
Respiratory System
Endocrine System
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Section:
Digestive System
Reproductive System
Excretory System
Lymphatic/Immune Systems
Section Outline
Section 35-2
35–2
The Nervous System
A. Neurons – cells that transmit impulses – bundles of neurons
make up nerves
(**structure next slide**)
1. Sensory – from environment to brain
2. Motor – from brain to muscles & glands
3. Interneurons – connect sensory & motor
B. Parts of a Neuron
1. Cell Body – nucleus here; most metabolic activity
2. Dendrites – small “branches”
3. Axon – a long “tail”
4. Myelin sheath – creates gaps called nodes
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Section:
A Neuron
Section 35-2
Nucleus
Axon terminals
Cell body
Myelin sheath
Nodes
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Section:
Axon
Dendrites
Section Outline
Section 35-2
35–2
The Nervous System (continued)
C. The Nerve Impulse
1. The Resting Neuron – balance of sodium and potassium
ions in cell (sodium out; potassium in) **next slide**
2. The Moving Impulse – begins with a stimulus from
environment or another neuron **advance 2 slides**
3. Threshold – all or nothing **domino example**
a. A few milliseconds after firing a neuron cannot receive
an impulse and then requires a stronger impulse to fire
again – only a few milliseconds before back to “normal”
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Section:
Figure 35-6 Resting Potential
Section 35-2
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Section:
Figure 35-7 An Impulse
Section 35-2
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Section:
Figure 35-7 An Impulse
Section 35-2
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Section:
Figure 35-7 An Impulse
Section 35-2
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Section:
Figure 35-7 An Impulse
Section 35-2
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Section:
Section Outline
Section 35-2
35–2
The Nervous System
C. The Nerve Impulse
1. The Resting Neuron – balance of sodium and potassium
ions in cell (sodium out; potassium in)
2. The Moving Impulse – begins with a stimulus from
environment or another neuron
3. Threshold – all or nothing
D. The Synapse
1. Axon to dendrite – between neurons
2. Use neurotransmitters to send impulse
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Section:
Figure 35-8 The Synapse
Section 35-2
Direction of Impulse
Dendrite of
adjacent neuron
Axon
Vesicle
Receptor
Axon
terminal
Synaptic cleft
Neurotransmitter
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Section:
Section Outline
Section 35-3
35–3
Divisions of the Nervous System
A. The Central Nervous System
1. Brain & Spinal Cord
2. Wrapped in meninges & surrounded by
cerebrospinal fluid
B. The Brain
1. The Cerebrum – voluntary activities of the brain
2. The Cerebellum – coordinates muscles
3. The Brain Stem – controls unconscious activity
a. Pons – upper part – sensory control
b. Medulla Oblongata – lower part – unconscious
control
4. The Thalamus and Hypothalamus
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Section:
Section Outline
Section 35-3
35–3
Divisions of the Nervous System (continued)
C. The Spinal Cord
D. The Peripheral Nervous System
1. Sensory
2. Motor
1. The Somatic Nervous System
2. The Autonomic Nervous System
1. Sympathetic
2. Parasympathetic
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Section:
Concept Map
Section 35-3
The Nervous
System
is divided into
Central nervous
system
Peripheral
nervous system
Motor
nerves
which consists of
that make up
Somatic nervous
system
Autonomic
nervous system
which is divided into
Sympathetic
nervous system
Go to
Section:
Parasympathetic
nervous system
Sensory
nerves
Figure 35-9 The Brain
Section 35-3
Cerebrum
Thalamus
Pineal
gland
Hypothalamus
Cerebellum
Pituitary gland
Pons
Medulla oblongata
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Section:
Spinal cord
Cross Section of the Spinal Cord
Section 35-3
Gray matter
Spinal nerve
Central canal
White matter
Meninges
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Section:
Section 35-3
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Section:
Section Outline
Section 35-4
35–4
The Senses
A. Vision
B. Hearing and Balance
1. Hearing
2. Balance
C. Smell and Taste
D. Touch and Related Senses
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Section:
Figure 35-14 The Eye
Section 35-4
Vitreous humor
Muscle
Lens
Fovea
Aqueous humor
Cornea
Pupil
Optic nerve
Iris
Blood vessels
Ligaments
Retina
Choroid
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Section:
Sclera
The Senses of Smell and Taste
Section 35-4
Olfactory
(smell) bulb
Taste
sensory
area
Olfactory
nerve
Thalamus
Cerebral cortex
Smell
receptor
Nasal cavity
Smell
sensory area
Taste bud
Taste
pore
Taste
receptor
Sensory
nerve fibers
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Section:
Figure 35-15 The Ear
Section 35-4
Anvil Stirrup
Hammer
Oval
window
Semicircular canals
Cochlear nerve
Cochlea
Bone
Auditory canal
Tympanum
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Section:
Round window
Eustachian tube
Section Outline
Section 35-5
35–5
Drugs and the Nervous System
A. Drugs That Affect the Synapse
1. Stimulants
2. Depressants
3. Cocaine
4. Opiates
5. Marijuana
6. Alcohol
7. Alcohol and Disease
B. Drug Abuse
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Section:
Commonly Abused Drugs
Section 35-5
Drug Type
Medical Use
Examples
Effects on the body
Stimulants
Used to increase alertness,
relieve fatigue
Amphetamines
Increase heart and respiratory rates;
elevate blood pressure; dilate pupils;
decrease appetite
Depressants
Used to relieve anxiety,
irritability, tension
Barbiturates
Tranquilizers
Slow down the actions of the central
nervous system; small amounts cause
calmness and relaxation; larger
amounts cause slurred speech and
impaired judgement
Opiates
Used to relieve pain
Morphine
Codeine
Act as a depressant; cause
drowsiness, restlessness, nausea
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Section:
Go Online
The latest discoveries in the nervous and immune systems
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For links on the nervous system, go to www.SciLinks.org and enter the
Web Code as follows: cbn-0352.
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Web Code as follows: cbn-0353.
For links on the senses, go to www.SciLinks.org and enter the
Web Code as follows: cbn-0354.
For links on drugs and drug abuse, go to www.SciLinks.org and enter
the Web Code as follows: cbn-0355.