Chapter 14_Lesson 1

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Chapter 14_Lesson 1

• Skeletal System

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Functions

• Provides a strong, stable, and mobile framework
  on which muscles can act
• Supports and protects internal organs
• Bones are storage centers for minerals such as
  calcium
• Manufacturing centers of the bodys blood cells
• Red bone marrow produces millions of red blood
  cells daily

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Structure

• 1. Axial skeleton 80 bones of the skull,
  spine, ribs, and sternum
• WHAT DO THESE PROTECT?
• 2. Appendicular skeleton 126
  bones of the shoulders, arms, hands, hips, legs,
  and feet

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TYPES OF BONES
Long Bones
Found in legs and arms
Example femur, humerus


Short Bones
Found in the wrists and ankles
Broad/wide as they are long


Flat Bones
Examples ribs and skull bones
Thin, flat shape
Serve to protect vital organs

Irregular Bones
Examples vertebrea
Have a shape that does not fit into any other category


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Cartilage

• Cartilage is a strong, flexible connective tissue
• Line the surface of joints and enable them to
  move smoothly, cushion adjoining vertebrea, and
  support the nose and ears
• Babies skeleton is mostly cartilage
• As the body grows, most cartilage cells are
  replaced by bone cells and minerals through
  ossification

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Joints

• The point at which 2 bones meet is called a joint
• Fixed joints (btw bones and skull)
• Small movement (vertebrea)
• Wide range (elbow, knee)
• IMAGINE YOUR LIFE WITHOUT JOINTS. WHAT
  ACTIVITIES WOULD YOU BE ABLE TO DO????

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Types of Joints
Ball-and-socket
Example shoulder and hip joints
Allows the widest range of movement Backward, forward, sideways, in a circle


Pivot
Example first 2 vertebrea
Allows rotation


Ellipsoidal
Example joint in your wrist
Allows all rotation except pivotal

Hinge
Examples fingers, elbow and knee
Allows bending and straightening


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How are all of these connected????

• The purpose is to reduce friction during movement
• Ligaments bone to bone
• Tendons muscle to bone muscle to muscle

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Caring for your skeletal system

• The body builds most of its bone mass in the teen
  years
• Nutrition foods rich in calcium and phosphorus
• Strong bones and rigidity
• Exercise
• Activity, especially weight bearing activity,
  increases bone mass
• and circulation

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Problems of the Skeletal System

• FRACTURES CLASSIFIED BY SHAPE/PATTERN OF BREAK

• Hairline fracture is incomplete, the 2 parts of
  the bone do not separate
• Transverse - fracture is completely across the
  bone.
• Comminuted bone shatters into more than 2 pieces

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Joint Injuries

• DISLOCATION

• TORN CARTILAGE

• Bone slips away from its normal position at a
  joint
• Never attempt to replace a dislocated bone
• Physician should put bone back and immobilize the
  joint so the tissue can heal

• Serious joint injury.
• Can result from a sharp blow or severe twisting
  of joint

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• OSTEOPOROSIS

• SCOLIOSIS

• Bone density decreases, causing bone to become
  brittle and easily fractured
• As teens, you have opportunity to prevent
  osteoporosis by exercising and eating enough
  foods rich in calcium

• Lateral/side-to-side curvature of the spine

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• ARTHRITIS

• Inflammation of a joint
• Pain, swelling, and redness
• Wear and tear on the joint