Dr.Ahmed Moussa
17-09-2009, 08:08 PM
بعد أما الإمتحانات خلصت والحمد لله
دلوقتي إن شاء الله هكمل المحاضرات التأهيليه .. Skeletal system
The skeleton s composed of two types of tissue cartilage & bone.
Cartilage:
It is softer than bone , less rigid & slightly elastic
Bone:
Rigid tissue hardened by calcium & phosphorus . The bone cells (osteocytes) are present in lacunae .
Forms of bones
The bone exists in two forms :
Compact (hard or ivory) bone:
It is hard , dense & forms the surface layer of all bones & the tubular shafts of long bone
Spongy , cancellus bone:
Its like a sponge which is usually filled with red bone marrow .
Parts of skeleton
Axial skeleton :
Skull :cranium 8 bones , face 14 bones , auditory ossicles 6 bones (28)
Hyoid:1 bone
vertebral column :33 vertebrae (7 cervical , 12 thoracic , 5 lumbar ,5 sacral , 4 coccygeal ) the sacral & coccygeal are fused in 2 masses so the count is (26)
sternum : 3 peices
ribs :12 pairs
Appendicular skeleton :
upper limb
shoulder girdle :2 scapula & 2 clavicle (4)
(2)arm bones :1 humerus in each side
forearm bones :1 ulna & i radius in each side (4)
wrist bones : 8 carpal bones in each wrist (16)
hand bones : 5 metacarpals in each hand (10)
finger bones : 14 phalanges in each hand , 2 in each tumb and 3 in each of other fingers (28)
lower limb
Hip girdle : hip bone one in each side (2)
Thigh bone : 1 femur in each thigh (2)
Leg bones : 1 tibia & 1 fibula in each leg (4)
Ankle & foot bones : 7 tarsala & 5 metatarsals in each foot . (24)
Toe bones : 14 phalages in each foot , 2 in the great toe and 3 in each of other toes (28).
functions of the skeleton :
1-Support the soft parts of the body.
2-gives shape to the body as a whole by the arrangement of bones.
3- allows movement by the muscles which pull the jointed bones into different directions .
4-lever action.
5-protiction of the dalicate parts of the body e.g.
the cranium proctects the brain.
the vertebral column protects the spinal cord.
the thoracic cage protects the heart and lungs.
6-bone marrow helps in the formation of blood.
7-a store for calcium and phosphorus for the time of need.
دلوقتي إن شاء الله هكمل المحاضرات التأهيليه .. Skeletal system
The skeleton s composed of two types of tissue cartilage & bone.
Cartilage:
It is softer than bone , less rigid & slightly elastic
Bone:
Rigid tissue hardened by calcium & phosphorus . The bone cells (osteocytes) are present in lacunae .
Forms of bones
The bone exists in two forms :
Compact (hard or ivory) bone:
It is hard , dense & forms the surface layer of all bones & the tubular shafts of long bone
Spongy , cancellus bone:
Its like a sponge which is usually filled with red bone marrow .
Parts of skeleton
Axial skeleton :
Skull :cranium 8 bones , face 14 bones , auditory ossicles 6 bones (28)
Hyoid:1 bone
vertebral column :33 vertebrae (7 cervical , 12 thoracic , 5 lumbar ,5 sacral , 4 coccygeal ) the sacral & coccygeal are fused in 2 masses so the count is (26)
sternum : 3 peices
ribs :12 pairs
Appendicular skeleton :
upper limb
shoulder girdle :2 scapula & 2 clavicle (4)
(2)arm bones :1 humerus in each side
forearm bones :1 ulna & i radius in each side (4)
wrist bones : 8 carpal bones in each wrist (16)
hand bones : 5 metacarpals in each hand (10)
finger bones : 14 phalanges in each hand , 2 in each tumb and 3 in each of other fingers (28)
lower limb
Hip girdle : hip bone one in each side (2)
Thigh bone : 1 femur in each thigh (2)
Leg bones : 1 tibia & 1 fibula in each leg (4)
Ankle & foot bones : 7 tarsala & 5 metatarsals in each foot . (24)
Toe bones : 14 phalages in each foot , 2 in the great toe and 3 in each of other toes (28).
functions of the skeleton :
1-Support the soft parts of the body.
2-gives shape to the body as a whole by the arrangement of bones.
3- allows movement by the muscles which pull the jointed bones into different directions .
4-lever action.
5-protiction of the dalicate parts of the body e.g.
the cranium proctects the brain.
the vertebral column protects the spinal cord.
the thoracic cage protects the heart and lungs.
6-bone marrow helps in the formation of blood.
7-a store for calcium and phosphorus for the time of need.