Physiology -Chap 7- Outline

(FIRST IS THE OUTLINE FROM MS. HATFIELD AND BELOW THE LINE ARE MY OWN NOTES (BEST IF USED TOGETHER))

Chapter 7 : The Skeletal System

• Divisions
  
  
• Axial: Consists of bones that lie around the longitudinal axial of the body.
  
  

  Includes: Skull, Hyoid, Auditory Ossicles, Vertebral Column, and the Thorax
  

• Appendicular: Consists of the bones that make up the upper and lower limbs and the girdles that connect the limbs to the axial
  
  

  Includes: Pectoral, Upper Limbs, Pelvic Girdle, and the Lower Lombs
  

• Girdles: Connect limbs to axial skeleton
  
  
• Types of Bones
  
  
• Long: Greater length than width, slightly curved for strength
  
  
  • Consists of shaft and a variable number of extremities
    
  • Mostly compact bone in shaft, spongy at ends
    
• Short: Somewhat cube shaped, width and length almost equal
  
  
  • Almost all spongy except at surface
    
• Flat: Thin
  
  
  • Consists of two nearly parallel plates of compact bone tissue enclosing spongy bone tissue
    
• Irregular: Complex shapes
  
  
  • Vary in amount of spongy and compact bone preasent
    
• Sesamoid:Only a few millimeters in diameter
  

Bone Surface Markings

• Depressions: Forms joints or allow the passage of soft tissue
  

Processes: Projections or outgrowths that either help form joints or serve as attachment points for connective tissue

* Know the table 7.2 *

• cleft palate
  
• cleft lip
  
  

Skull

• Function: Protects brain, blood vessels, lymphatic vessels, and nerves through the attachment of their inner surfaces
  
  

  Also provide attachment for some muscles that produce facial expressions
  

• Number of Bones Total:
  
  
• Cranial: Form the cranial cavity which encloses and protects the brain
  
• Facial: Forms the face
  

Vertebral Column

Physiology-

Total number: Cervical

Thoracic

Lumbar

Sacral

Coccygeal

Intervertebral discs:

Characteristics of a Typical Vertebrae-

Body-

Vertebral arch-

Processes-

• transverse-
  

• spinous-
  

Facets-

• inferior
  
  

  2. superior
  

Cervical Vertebrae:

Number:

Special characteristics:

Special movements:

Thoracic Vertebrae

Number:

Special characteristics:

Special movements:

Lumbar Vertebrae

Number:

Special characteristics:

Special movements:

Sacrum

Number:

Special characteristics:

Special movements:

Coccyx-

Number:

Special characteristics:

Special movements:

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Divisions of the Skeletal System

• The bones of adults are grouped into two main categories:
  
  
  • Axial
    
  • Appendicular
    
• The girdle connect the limbs of the appendicular to the axial bones
  
  

  Note: Functionally the ossicles in the ear are not a part of the axial, but are included for convenience
  

  Types of Bones
  

• All bones can be classified into five main types based on shape
  
  
  • Long: Curved for strength
    
    
    • Curve absorbs the stress of the bodies weight at several different points (like an arch)
      
    • If bones were straight the weight would not be even distributed and would be more easily fracture
      
  • Short
    
  • Flat: Afford more protection and provide extensive areas for muscle attachment
    
  • Irregular: Cannot be grouped into any other areas
    
  • Sesamoid: Develop in certain tendons where there is considerable friction, tension, and physical stress
    
    
    • Vary in number from person to person
      
    • Not completely ossified
      
    • Protect tendons from excessive wear and tear
      
    • Often change the direction of pull of a tendon, improve mechanical advantage at a joint
      
• There is one other type of bone that is classified by location rather than shape
  
  
  • Sutural bone
    
    
    • Small bones located in sutures (immovable joints) between cranial bones
      
      

      
      

  Bone Surface Markings
  

• Bones have surface markings: structural features adapted for specific functions
  
  
  • Most not present at birth, but tension causes them
    
• Two major types of surface markings
  
  
  • Depressions and openings
    
  • Processes
    
    

    
    

  Skull
  

• Has 22 bones
  
• Rests of superior end of the vertebral column
  
• The bones of the skull are grouped into two categories:
  
  
  • Cranial bones:
    
    
    • Frontal bone, two parietal bones, two temporal bones, the occipital bone, and sphenoid bone, and the ethmoid bone
      
  • Facial bones:
    
    
    • Two nasal bones, two maxillae, two zygomatic bones, the mindible, two lacrimal bones, two palatine bones, two inferior nasal conache, and the vomer
      

  General Features and Function
  

• Also forms smaller cranial cavities
  
• Certain skull bones contain cavities called paranasal sinuses that are linked with mucous membranes and open into the nasal cavity
  
• Other than the auditory ossicles the mandible is the only movable bone of the skull
  
  

  Cranial Bones
  

  Frontal Bone
  

• Frontal bone
  
  
  • Forms forehead, roof of orbits, ad most of the anterior part of the cranial floor