Axial skeleton:skull (cranium and facial bones) hyoid bone (anchors tongue and muscles

associated with swallowing) vertebral column (vertebrae and disks) bony thorax (ribs and sternum)

Appendicular skeleton:pectoral girdle (clavicles and scapulae)upper limbs (arms)pelvic girdle (sacrum, coccyx)lower limbs (legs)

Articulation- where joints meet, connect, and are formed.

Regions of the Human Skeleton

22 bones in skull6 in middle ears1 hyoid bone26 in vertebral column25 in thoracic cage

4 in pectoral girdle60 in upper limbs60 in lower limbs2 in pelvic girdle

206 Bones in a Human Adult Skeleton

The Axial SkeletonThe Axial Skeleton

Slide 5.20a

Forms the longitudinal part of the body

Divided into three parts

Skull

Vertebral column

Bony thorax

The Axial SkeletonThe Axial Skeleton

Bones of the Skull- Frontal View Bones of the Skull- Frontal View (10.4)(10.4)

Cranium:-8 sutured bones-Encases brain-Muscle attachment-Sinuses

Facial bones: -13 sutured bones-1 mandible

Bones of the Skull- Lateral View Bones of the Skull- Lateral View (10.1) (10.1)

Human Skull: Human Skull:

Inferior Superficial View (10.2)Inferior Superficial View (10.2)

Human Skull: Human Skull:

Superior View of the Floor of Cranial Cavity (10.3)Superior View of the Floor of Cranial Cavity (10.3)

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

The Fetal Skull: Superior View (10.9)•Skull bones are still incomplete •Fontanels (“little fountain”):

•Unossified remnants of fibrous membranes•Pulse can be felt surging in these “soft spots”•Allow infants head to be compressed slightly during birth•Accommodate brain growth in fetus & infant

•Anterior fontanel remains soft until 1.5-2yrs of age•Others are replaced by bone by the end of the first year

Fetal Skull: Lateral View (10.9)

Paranasal Sinuses Paranasal Sinuses (10.6)(10.6)

• Mucus lined, hollow, air-filled portions of bones surrounding the nasal cavity

• Mucoase of sinus help to warm and humidify inspired air

The Hyoid BoneThe Hyoid Bone

The only bone that does not articulate with another bone

Anchored by narrow stylohyoid ligaments to syloid process of temporal bone.

Serves as a moveable base for the tongue

Figure 5.12

The Vertebral ColumnThe Vertebral Column Vertebrae separated by

intervertebral discs

Spine has a normal curvature

Vertebrae vary in size and morphology

Each vertebrae named according to location:

7 cervical vertebrae

12 thoracic

5 lumbar

1 sacrum (5 fused)

1 coccyx (4 fused)

Structure of a Typical VertebraeStructure of a Typical Vertebrae

•Ribs, thoracic vertebrae, sternum, costal cartilages•True ribs -directly attached to sternum (1st seven pairs•Three false ribs are joined to the 7th rib•Two pairs of floating ribs

Thoracic CageThoracic Cage

Shoulder Girdle & Upper Limb

Pelvic Girdle

Male v. Female Pelvis

Human Leg Bones