The Skeleton

BIO 231

Anatomy and Physiology

 

Parts of the Skeleton

Axial -  80 bones

Skull, vertebral column, bony thorax

Appendicular - 126 bones - bones of the limbs and girdles

 

The Skull

Composed of cranial & facial

22 total bones

Cranium - protects brain - site of attachment for                     and neck muscles

Facial bones - framework of the face

Contain cavities fro taste, sight and smell

Openings for air and food passage

secure teeth

Anchors facial muscles - show our                               

 

The Skull

Most bones are flat

Sutures - interlocking joints between bones of the skull

Serrated appearance

85 named openings

Foramina, canals, fissures, etc.

Passageways for spinal cord, blood vessels and                                    nerves

 

Cranium

8 bones

 Paired - parietal & occipital

Unpaired - frontal, occipital, sphenoid and                              bones

 

Frontal Bone

 

 

 

Parietal Bones

 

 

 

 

Occipital Bone

 

 

 

 

Temporal Bones

 

 

Sphenoid Bone

 

 

 

 

 

Ethmoid Bone

 

 

 

 

Facial Bones

14 bones

Only mandible and volmer are                          

Maxillae, zygomatics, lacrimals, palatines, and inferior conchae are paired bones

 

Mandible

U shaped - largest/strongest bone of the face

 

Maxillary Bones

Fused                                                  - form upper jaw

 

Zygomatic Bones

 

 

 

 

Nasal Bones

 

 

 

Lacrimal Bones

 

 

 

 

Palatine Bones

 

 

 

 

Volmer

 

 

 

 

Inferior Nasal Conchae

 

Hyoid Bone

Does not articulate with any other bone

Lies inferior to the mandible in the anterior neck

Anchored by stylohyloid ligament to the styloid processes of the temporal bones

Acts as movable base for the                               

It body and greater horns are attachment points for muscles that raise and lower the larynx during speech and swallowing

 

Hyoid Bone

 

 

 

Vertebral Column

About 70 cm (28 inches) long)

4                                             

Cervical - 7 vertebrae

Thoracic - 12 vertebrae

Lumbar - 5 vertebrae

Sacrum - 5 fused

Coccyx - 3-4 fused vertebrae

 

Vertebral Column

 

 

 

 

Vertebral Column

 

 

 

 

Ligaments

Anterior and posterior longitudinal ligaments -major supporting ligaments

Intervertebral Discs

Shock                                                

2.5 % of the height of the vertebral column

Inner gelatinous nucleus pulposus - rubber ball like

Elastic and compressible

Annulous fibrosus - strong collar of collagen fibers superficially and fibrocartilage internally

 

Ligaments and Discs

 

 

 

 

 

General Structure of a Vertebrae

Vertebrae Comparison

 

 

 

 

 

Cervical Vertebrae

 

 

 

 

 

C1 - Atlas

 

 

 

C2 - Axis

 

 

 

Thoracic Vertebrae

 

 

 

 

Lumbar Vertebrae

 

 

 

Sacrum

 

 

 

Bony Thorax

 

 

 

 

True Ribs

 

 

 

 

Appendicular Skeleton

Pectoral girdle & upper limb

Pelvic girdle & lower limb

 

Pectoral Girdle

 

Pectoral Girdle & Upper Limb

 

 

 

Humerus

 

 

 

Bones of Forearm

 

 

 

 

Bones of the Forearm

 

 

 

 

Bones of the Hand

 

 

 

 

Pelvic Girdle

 

 

 

Female and Male Pelves

 

 

 

Patella and Femur

 

 

 

Tibia and Fibula

 

 

 

Bones of the Foot

 

 

Arches of the Foot

Due to the interlocking shapes of the foot bones &                              & the pull of some tendons during muscle contraction