skeletal system (studied)

function of skeletal system

support and protection

body movement

blood cell formation (Hematopoises) in bone marrow

storage of inorganic materials like salt, calcium, and potassium

206 bones in adulthood

two main divisions:;

Axial skeleton

appendicular skeleton

axial skeleton

head, neck, trunk

appendicular skeleton

limbs and girdles, bones of hands

Ephysial plate

where cartilage grows, divides, deteriorates, and are replaced by bone (ossification) by osteoclasts, forming spongy bone and lengthening the bone sto

Osteoclasts

osteoclasts enlarge the medullary cavity as the bone grows

endochondreal Ossification

1. bone template formed from hyaline cartilage and enlarges through proliferation of chondrocytes ,a collar bone is formed via intramembranous ossification

2. blood vessels penetrate primary ossification center and osteoblasts and osteoclasts.

3. the center is hollowed out for a narrow cavity and edges to ossify

4. remodeling primary ossification center continues, while secondary ossification center forms

   1. a fully developed bone is still growing, but has cartilage on surfaces of articulation and epiphyseal plates

steps to healing a bone

1. formation of hematoma

2. formation of a fibrocartilage callus

3. formation of a bony callus

4. bone remodeling by osteoclasts