Skeleton of Human

Skeleton of Human

v Skull: Has total 29 bones

·       Total cranial bones : 8

Frontal -1, parietal- 2, temporal-2, occipital-1, sphenoid-1

Ethmoid-1

Middle ear in human is enclosed by temporal bone

·        Total facial bones: 14

Nasals-2, maxillae-2, mandible-1, vomer-1, palatine-2, lachrymal-2, inferior nasal-2, zygomatic (cheek bone) - 2

·        Ear ossicles: 6( 3 in each ear)

·        Single hyoid bone at the base of tongue

·        The joint of skull bone is called suture and the air filled cavities in the skull bone is called sinuses

·        Coronal suture joins frontal and parietal bone

·        Lambdoidal suture joins parietal and occipital bone

·        Squamous suture joins parietal and temporal bone

·        Saggital suture joins two parietal bones

·        Sella turcica for lodging pituitary gland is found in sphenoid bone

·        Mastoid process is found in temporal bone

v Vertebral column:

 Total no vertebra is 33 in infants and 26 in adults. In adult the sacral and coccyx vertebra gets fused

·        Cervical- 7

·        Thoracic- 12

·        Lumbar- 5

·        Sacral- 1(5 in infants)

·        Coccyx- 1(4 in infants)

v Sternum: single piece, flat and has Xiphoid process

v Ribs: 12 pairs

·        True: 7 pairs ( 1^st- 7^th)

·        False/pseudo: 3 pairs ( 8^th,9^th,10^th)

·        Floating: 2 pairs (11^th-12^th)

v Pectoral girdle: total 4 bones : 2 clavicle and 2 scapula

v Pelvic girdle: 2 innominate bones, Innominate= (pubis+ilium+Ischium)

v Fore limbs: total 60 bones(both hands) : humerus-2,radius-2,ulna-2,carpals-16,metacarpals-10 and phalanges- 28

v Hind limbs: total 60 bones(both legs) : femur-2, tibia-2,fibula-2,patella-2,tarsals-14,metatarsals-10,phalanges-28

Note:

·        Total bone in adult : 206

·        Total bone in infant: 213

·        Ligament joins bone to bone and tendon joins bone to muscle

        ¨        Extra knowledge:

·        Clavicle is first bone to ossify

·        Mandible is second bone to ossify

·        Sinuses are the air filled cavity of skull bones.there is 4 sinuses in human, they are: maxillary sinus, frontal sinus, sphenoid sinus and ethmoid sinus. The inflammation of sinus is called sinusitis( pinas)

·        Fontanelle is the membranous space between the cranial bones in infants.

·        Knee joint is largest joint of human body

·        Arthritis is the inflammation od joint

·        Tuberculosis of back bone is called pott’s disease

·        Deficiency of vitamin D in children causes rickets

·        Deficiency of vitamin D in adult causes osteomalacia

·        The decrease in bone mass due to deficiency of calcium is called osteoporosis

·        Osteomyelitis: the inflammation of bone by staphylococcous aureus

·        Gout is the disease of joint caused by deposition of sodium urate crystal in joints

·        Osteosarcoma is the cancer of bone

·        Osteogenesis imperfect : also called brittle bone syndrome is genetic disorder resulting in failuse of ossification of bone

·        Polio caused by picorna virus caused bone deformities in limbs

·        End of long bones are made up of hyaline cartilage

·        Redbone marrow is present on epiphysis of long bone and yellow bone marrow in metaphysis

·        Long bones of mammal consist of Haversian canal. The two haversian canal are joined by volkmans canal