Transcript The Skeletal, Muscular and Integumentary Systems

The Skeletal System
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Supports the body
Protects internal organs
Aids in movement
Stores minerals
Make blood cells
The Skeleton
206 bones
 Bone is living tissue
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◦ Contains living bone cells, blood vessels and
nerves.
Bone marrow stores fat and makes blood
cells
 Bone starts out as cartilage and ossifies
into bone.
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The Skeleton
Figure 36-3 The Structure of Bone
Section 361
Spongy bone
Haversian
canal
compact bone
Periosteum
Compact
bone
Bone
marrow
Spongy bone
Osteocyte
Artery
Vein
Periosteum
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Elastic ligaments
hold bones together
at joints.
Cartilage protects
bones at joints.
◦ Hinge joints – elbow
and knee
◦ Ball and socket joint
– shoulder and hip
◦ Pivot joint – neck
◦ Gliding joint – wrist
and ankle
Joints
Section 361
Muscle
Tendon
Femur
Patella
Bursa
Ligament
Synovial fluid
Cartilage
Fat
Fibula
Tibia
Arthritis – inflammation of joints
 Osteoporosis – mineral loss; weakening
 Sprains – ligaments are stretched or torn.
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Skeletal Disorders
Muscular System
The only tissue that contracts.
 Three types:
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◦ Skeletal = attached to bones; voluntary
◦ Cardiac = in the heart; involuntary
◦ Smooth = make up digestive tract, blood
vessels and other organs; involuntary
Muscular Tissue
Section 362
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Protein fibers called
actin and myosin
slide over each
other.
This requires lots of
energy.
◦ Muscle cells have lots
of mitochondria, like
nerve cells.
Muscle Contraction
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Muscles contract
when nerves tell
them to.
Muscle Contraction
Inelastic tendons attach muscle to bone.
 Muscles can only pull, not push.
 Muscles work in opposing pairs to move a
bone.
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◦ One muscle bends the joint and another
muscle straightens the joint.
Movement
Section 362
Movement
Movement
Biceps (relaxed)
Triceps (contracted)
Biceps (contracted)
Triceps (relaxed)
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Regular exercise keeps the muscles in a
partial state of contraction called muscle
tone.
◦ This is important to survival.
Muscle Tone
Integumentary System
Hair, skin, nails
First line of defense against disease.
 Helps regulate body temperature.
 Aids in waste removal (excretion).
 Protects against UV radiation.
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Skin
Section 363
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UV radiation can cause mutations in skin
cells resulting in abnormal growth.
◦ The tendency towards skin cancer is hereditary.
Skin Cancer
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Hair provides protection from UV radiation
and filters particulates from the nose, ear
and eyes.
◦ Hairs as well as attached skin cells are used as
forensic evidence.
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Nails grow from the base called the root.
◦ Some nails get invaded by a fungus and look
nasty.
Hair and Nails