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The Nervous System
What is the nervous system?
o Control Center
o Communications Network
Responsibilities:
- Thoughts
- Senses
- Movement
- Balance
- Automatic Responses
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The Nervous System Is Divided Into 2 Main Parts
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The Central Nervous System (CNS)
o The Brain & Spinal Cord
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The Peripheral Nervous System (PNS)
o Nerves That Link Body With CNS
Sensory Input:
Monitor both external
and internal
environments.
Integration: Process
the information and
often integrate it with
stored information.
Motor output: If
necessary, signal
effector organs to make
an appropriate
response.
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Nerves: Bundles of Tissue
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Three Parts to a Neuron
o Cell Body (the brain of a neuron)
o Dendrites (receives)
o Axon (carries signals)
Synapse: the joining of two neurons (one sending, one receiving).
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The axons do not touch.
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Separation: synaptic cleft.
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Neurotransmitters: chemicals released
by axons that travel through the
synaptic cleft.
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Released by Axon
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Travels Across Synaptic Cleft
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Binds to Receptors on Next Nerve
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The Main Control Center (CNS)
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Three Major Areas
o Cerebrum
o Cerebellum
o Brain Stem

Center for thought, imagination, emotion, activity.
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Two Halves (Hemispheres)
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Each Half: 4 Lobes
o Frontal
o Temporal
o Parietal
o Occipital
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Frontal Lobe:
Speech, Thought, Taste, & Movement
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Parietal Lobe:
Touch
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Temporal Lobe:
Hearing
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Occipital Lobe:
Vision
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Balance & Coordination

Smooth's Movement for
Fine Coordination
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Secondary: language, attention, regulating fear & pleasure
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Guides Signals From Brain & Spinal Cord
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Structurally Continuous
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Three Parts
o Midbrain
o Pons
o Medulla Oblongata
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Smallest Portion of Brain
Relays Information
Vision
Hearing
Motor Control
Sleep
Arousal
Alertness
Temperature
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Latin: bridge
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Relays information
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Sleep
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Arousal
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Automatic Functions
o
o
o
o
o
o
o
Heartbeat
Breathing
Digestions
Swallowing
Vomiting
Sneezing
Coughing

Final Link Between Brain & Spinal Cord

Relays Information

Automatic Actions
o Heartbeat
o Breathing
o Digestions
o Swallowing
o Vomiting
o Sneezing
o Coughing
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Spinal Cord: thick cord of nerve tissue
Spine: protective bone structure
 Spine:
protective bone structure
o 33 vertebrae
o 9 fused
o 24 articulating (moving)

Categorized
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Lower  Bigger Vertebrae
Which 9 vertebrae's are fused? Why?
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C1 to C7
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T1 to T12
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L1 to L5
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Sacrum
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Coccyx
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The Skeletal System
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What is the Skeletal System?
o All 206 Bones in Body

What is the Purpose?
o Give Body Shape & Support
o Protection for Vital Organs
o Produces Blood Cells
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Epiphysis: Ends of Bone
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Diaphysis: Middle of Bone
Articular Cartilage: cartilage covering articular surfaces (joints)
Purpose: Helps provide support/cushion in joints.
Cancellous Bone (Spongy): a highly vascular bone that contains red bone marrow,
typically located at the end of bones. It contains high surface area, but less density.
Purpose: makes bone light and strong, while producing red blood cells.
Epiphyseal Plate: contains growing bone in pre-adult years. As you age, the bone
elongates. Once, you have stopped growing, this plate solidifies.
Marrow Cavity: the cavity in the diaphysis of a long bone containing the marrow.
Yellow Bone Marrow: soft tissue, made mostly of fat, that stores energy (diaphysis).
Red Bone Marrow: soft tissue that aids in the production of red blood cells (epiphysis).
Periosteum: membrane that lines the outer layer of bones.
Purpose: outer layer serves as an
attachment point for muscles and bones
through tendons and ligaments.
Purpose: inner layer will help breakdown
and build bone.
Compact Bone: provides support and is made up of living bone cells, minerals,
protein fibers, blood vessels, and nerves.
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Joints: the joining of two or more bones.
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Types of Joints:
o Fixed
o Semimovable
o Pivot
o Ball-and-Socket
o Hinge
o Ellipsoidal
206 Total Bones = Lots of Joints
A fixed joint does not allow movement.
A Semimovable joints allows
for little movements.
A pivot joint is a joint in which one
bone rotates around another bone.
A ball-and-socket joint allows for great
movement in any direction.
A hinge joint allows for back
and forth movement.
An ellipsoidal joint allows for all
movement except for rotation.
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206 Bones
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Career Field  How Much You Need to Know

Health Class  The Basics
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The Muscular System
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All Movement of Body
o Running, Walking, Etc.
o Breathing
o Digesting Food
o Pumping Blood
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Protect Joints
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Protect Organs
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Create Heat
Muscle Fibers: bundles of long Paired Strains of Protein.
Actin (thin): Protein, Works with Myosin for Contraction.
Myosin (thick): Protein, Works with Actin for Contraction (Motor).
Sarcomere: the basic unit of a muscle fiber (Z Line to Z Line)
M-Line: Middle of Sarcomeres, Anchors the Myosin
Z-Disc: Beginning & End of Sarcomeres, Anchor Actin
A Band: the entire length of the myosin.
I Band: the zone of actin that is not connected to myosin.
H Zone: the zone of myosin that is not connected to actin.
(located inside the A Band)
Skeletal Muscle: striated (striped), move
voluntarily.
Smooth Muscle: involuntary movements.
Cardiac Muscle: only found in the heart.
How can you tell the difference?
VS
They appear similar, but look for the intercalated disks.
Intercalated Disks: connects adjacent cardiac cells, allowing for
faster electric transfer.
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Approximately 639 to 850 Muscles in Body
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Debate
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Basics
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How are muscles named?
o Size
Names started developing
in the 1500’s by Greek
and Roman Anatomists.
o Location on Body
o Relation to Bone
o Origin & Insertion
o Direction of Fibers
Many words contain
Greek and Latin roots.
Many more muscles in
the upper leg, but we will
focus on the quads.
Many more muscles in
the upper leg, but we will
focus on the Hamstrings.
Four Total Parts
o Gluteus Maximus
o Gluteus Minimus
o Gluteus Medius
o Tensor Fasciae Latae
Tibialis Anterior
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The Circulatory System
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The Respiratory System
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The Digestive System
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The Excretory System
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The Immune System
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The Endocrine System
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The Male Reproductive System
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The Female Reproductive System