Transcript Unit 10 Chapter 34 Protection, Support, and Locomotion

Unit 10
Chapter 34
Protection, Support,
and Locomotion
Skin: the Body’s Protection
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Integumentary System
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Contains skin and its related parts—hair, nails
& glands
Functions:
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Regulates body temperature
Receives stimuli from environment
Produces vitamin D
Protection of underlying tissues
Skin: the Body’s Protection
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Epidermis:
 Outer layer of skin,
composed of dead,
flattened cells
 Contains Melanin,
a pigment that
colors the skin &
protects cell from
damage by
radiation
Skin: the Body’s Protection
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Dermis
Inner, thicker
portion of the skin
Contains blood
vessels, nerve
endings, hair
follicles, sweat &
oil glands
Skin: the Body’s Protection
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Hypodermis
(subcutaneous layer)
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Below the dermis
Contains primarily of fat
for cushioning &
insulation
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Bones: the Body’s Support
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Skeletal System
divisions:
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Axial skeleton
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Includes the skull,
vertebrae, ribs &
sternum
Appendicular
skeleton
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Includes bones of the
arms & legs, and
shoulder & hip bones
Bones: the Body’s Support
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Skeletal system functions:
Protection
Support
Attach muscles
Produce blood cells
Store minerals
Bones: the Body’s Support
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Joints
 Where two bones
meet
 Facilitates the
movement of
bones in relation to
one another
Bones: the Body’s Support
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Ligaments
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Connective tissue
that attaches one
bone to another
Tendons
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Connective tissue
that attach muscles
to bones
Bones: the Body’s Support
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Spongy bone
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Compact bone
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Soft bone containing many
spaces filled with red marrow
Dense bone with an inner cavity
containing yellow marrow
Haversian system
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Circular area in compact bone
containing blood vessels,
nerves, and living cells called
osteocytes
Muscles for Locomotion
Muscles for Locomotion
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Smooth muscle
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Involuntary movement
Found in hollow body
organs, i.e. stomach,
arteries, iris of eye
Spindle-shaped cells,
non-striated, one
nucleus per cell
Muscles for Locomotion
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Cardiac muscle
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Involuntary movement
Found only in the heart
Branching, striated
(striped) cells, with one
nucleus per cell
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Muscles for Locomotion
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Skeletal muscle
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Voluntary movement
Found attached to bones,
i.e. biceps, triceps,
hamstrings, etc
Long, striated (striped)
cells, with many nuclei
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Extensor and flexor muscles
Click on image to play video.
Muscles for Locomotion
Common
Skeletal
muscles
Muscles for Locomotion
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Muscle contraction:
Muscle fibers (cells) are made up of smaller
units called myofibrils
Myofibrils contract (shorten) as filaments, called
myosin & actin, slide toward one another
Sliding filament model