1. The Skeletal System

2. Functions of skeleton Gives support and shape to body
Protects vital organs
Provide rigid structure for muscle attachment & leverage
Manufacture blood cells
Calcium & other mineral salts are stored

3. Types of skeletons Axial Skeleton Appendicular system
126 bones of the extremities, including the scapulae, clavicles, and pelvis
80 bones of the head, thorax, and trunk

4. Bone Made up of different types of tissue
1/3 organic (living)- gives elasticity
2/3 inorganic (nonliving)- provides hardness & strength
Two types
Compact bone
- makes up hard, dense outer shell
- completely cover the bone
- thick along the shaft
- thin at ends of long bone
Cancellous bone
- porous & spongy inside potion
- arranged in a pattern that resists stress &strain

5. Bone structure Epiphysis area at each end of long bone Diaphysis
wider than shaft
adult bone: osseous
growing bone: cartilaginous epiphyseal plate
Diaphysis
main shaft of bone
mostly compact bone
center medullary canal
Endosteum- membrane that lines medullary canal
it contains osteoclasts
Metaphysis
flared area at ends of diaphysis
made mostly of cancellous bone
Supports epiphysis

6. Periosteum Thin fibrous membrane
Cover all the bone except articular surface
Provides nourishment, promotes bone growth, and assists with repair
Serves an attachment for tendon & ligaments
Two types epiphysis found in children
Pressure epiphysis
-located at end of long bones
-receive pressure from opposing bone
-this is where growth of long bone occur
Traction epiphysis
-located where tendons attach to bone
-subjected to pulling or traction

8. Types of Bone Long bones Short bones Flat bones Irregular bones
Sesamoid bones

9. Long bones Largest bones in the body
Makes most of appendicular skeleton

10. Short bones Have more equal dimensions of height, length & width
Have great deal of articular surface
Usually articulate with more than one bone
Composition similar to long bones
e.g.
Carpals
Tarsals

11. Flat bones Have very broad surface But not very thick
Made of 2 layers of compact bone with cancellouse bone & marrow in between
e.g. Illium
scapular

12. Irregular bones Variety of mixed shapes
Composed of cancellous bone and marrow in case in a thin layer of compact bone
e.g. vertebrae
sacrum

13. Sesamoid bones
Small bones located where tendons cross long bones in extremities
They develop within the tendon & protect it from excessive wear
e.g. patella

14. Common skeletal pathologies
Fracture
Osteoporosis
Osteomyelisis

15. Thank You