5 functions of Skeletal System
- Support: structural framework of the body
- Movement: attachment site for muscles
- Protection of internal organs
- Hemopoiesis: red bone marrow produces blood cells
- Storage of calcium, phosphorus, and fat
Yellow bone marrow stores…
Fat
ToB: Long
longer than wide
-Ex. Femur, Humerus
ToB: Short
Cube-shaped
-Ex. Carpals, Tarsals
ToB: Flat
Thin
-Ex. Cranium, ribs, sternum
ToB: Irregular
Complex Shapes
-Ex. Vertebrae, Facial Bones
ToB: Sesamoid
Completely enclosed within a tendon
-Ex. Patella
ToB: Sutural Bones
Small bones located within cranial sutures
-Ex. Joints
LB: Disphysis
Long shaft
LB: Epiphysis
Ends of bones
-Proximal and distal
LB: Metaphysis or epiphyseal plate
Area of cartilage where bones grow in length
LB: Articular Cartilage
A thin layer of cartilage covering epiphysis to reduce friction in joints
LB: Periosteum
Tough outer covering around the bone
LB: Medullary (marrow) Cavity
Hollow inside of the bone
LB: Endostem
The membrane which lines the marrow cavity
Osteogenic Cells
Unspecialized cells which undergo mitosis become osteoblasts
Osteoblasts Cells
Bone-building cells
-(Secrete matrix)
Osteocytes Cells
Mature bone cells which maintain bone tissue
Osteoclasts Cells
Bone-destroying cells
-Remodeling
Compact Bone`
- Looks like a solid, hard layer of bone
- Makes up the shaft of long bones and the external layer of all bones
- Resists stresses produced by weight and movement
Osteology
Study of Bones
CB: Osteon (Haversian System)
The basic unit of compact bone
CB: Haversian (central) Canal
Contains blood vessels and nerves
CB: Lamellae
Concentric rings of matric
