2.bones.pdf

 Bones Function of bones  Protection of certain organs "skull protect the brain & eye & ear"  Support: skeleton provide framework for the body  Storage of minerals as calcium  Hematopoiesis::...

 Bones Function of bones  Protection of certain organs "skull protect the brain & eye & ear"  Support: skeleton provide framework for the body  Storage of minerals as calcium  Hematopoiesis:: y Blood cells are formed in the red bone marrow w da en H R. D Anatomist “Bone”  Classification of bone According to bone site Axial skeleton: 1. Skull: protects the brain 2. Thoracic Cage: Consists of:  Sternum (anteriorly).  12 pairs of ribs (laterally). y  12 Thoracic vertebrae (posteriorly). 3. Vertebral Column: w  Distribution: o 7Cervical o 12Thoracic o 5Lumbar da en o 5Sacral “fused” o 3 or 4 Coccygeal “fused” H R. D Anatomist “Bone” Appendicular skeleton: Upper limb y o Girdle: Shoulder girdle formed of: Clavicle & scapula w o Proximal part: The arm contains “Humerus” da o Middle part: The forearm contains Radius “lateral” & Ulna “medial” en o The distal part: Hand contains  8 Carpal bones  5 Metacarpal bone H  14 Phalanges R. D Anatomist “Bone” Lower limb y o Girdle: pelvic girdle formed of: 2 hip bones w o Proximal part: The thigh contains “femur” da o Middle part: The leg contains fibula “lateral” & tibia “medial” en o The distal part: foot contains  7 Tarsal bones  5 Metatarsal bones H  14 Phalanges R. D Anatomist “Bone” According to bone shape  Long bones: as humerus, ulna, radius, metacarpus, …. y Characterized features of long bone: w o They have 2 ends “epiphysis” & shaft “diaphysis” o The epiphysis is covered by hyaline cartilage da o The diaphysis is covered by strong fibrous membrane “periostium or cortex” which is considered site for growth in width o Epiphyseal cartilage is the site of bone growth in lenght o Metaphysis is region of the shaft close of epiphyseal cartilage en o 4 arteries supply long bones: epiphyseal artery- metaphyseal artery - periosteal artery - nutrient artery  Short bones: as carpal & tarsal bones.   H Flat bones: as scapula & skull cap, sternum & ribs Irregular bones: as vertebrae, skull base & hip bone. R.  Pneumatic bones: air filled bones as facial bones (maxilla, sphenoid, frontal, ethmoidal)  Sesamoid bones: bone embedded in tendon of muscle as Patella & fabella & pisiform D Anatomist “Bone”  y w da en H R. D Anatomist “Bone” According to structure  Cancellous “spongy” bone: as the epiphyses of a long bone  Compact bone: as the cortex “periostium” of a long bone. y According to ossification / development w  Cartilaginous “endochondral” ossification:  Soft membranous tissue become cartilage then ossify da  Examples: all bones of the limbs except shaft of the clavicle.  Membranous ossification: en  Soft membranous tissue ossifies directly  Examples: shaft of the clavicle & skull cap & bones of face H R. D Anatomist “Bone”