Oxygenation

Skeletal System

• Consists of cartilage and bone
• Cartilage is a special type of non-vascular connective tissue with three types:
  • Hyaline cartilage (articular surface)
  • Fibrous cartilage (discs)
  • Elastic cartilage (auricle)
• Bone is a hard, calcified type of connective tissue with functions:
  • Protects organs
  • Offers support, protection, and flexibility to organisms
  • Forms blood cells
  • Stores calcium

Gross Types of Bones

• Long bones: have two ends and a shaft (e.g., humerus and femur)
  • Consist of epiphysis, metaphysis (includes epiphyseal plate in growing bones), and diaphysis (shaft)
• Short bones: have no epiphyses and shaft (e.g., carpal and tarsal bones)
• Flat bones: bones with two surfaces (e.g., cranial bones, scapula, ribs, sutural bones)
• Irregular bones: bones with no definite shape (e.g., vertebrae, face bones)
• Sesamoid bones: associated with tendons of upper and lower limbs (e.g., patella is the largest sesamoid bone)
• Pneumatic bones: certain bones of the skull containing air cavities (e.g., frontal, sphenoid, ethmoid, mastoid part of temporal, and maxillae)

Bone Markings

• Surface features of bones:
  • Sites of attachments for muscles, tendons, and ligaments
  • Passages for nerves and blood vessels
• Types of bone markings:
  • Fissure
  • Foramen
  • Fossa
  • Sulcus
  • Meatus
  • Condyle
  • Facet
  • Head
  • Epicondyle
  • Line
  • Spinous process
  • Trochanter
  • Tubercle
  • Tuberosity

Axial Skeleton

• Includes:
  • Skull
  • Vertebral column
  • Ribs
  • Sternum
  • Hyoid bone
• Functions:
  • Protects organs
  • Offers support, protection, and flexibility to organisms
  • Forms blood cells
  • Stores calcium

Skull

• Formed by 22 bones, descriptively divided into:
  • Upper cranium and lower facial skeleton
• The cranium bones:
  • Frontal
  • Parietal (2)
  • Temporal (2)
  • Occipital
  • Sphenoid
  • Ethmoid
• The facial bones:
  • Zygomatic bones (2)
  • Maxillae (2)
  • Nasal bones (2)
  • Lacrimal bones (2)
  • Vomer (1)
  • Palatine bones (2)
  • Inferior conchae (2)
  • Mandible (1)

Cranial Sutures

• Types of cranial sutures:
  • Sagittal suture: between the parietal bones
  • Coronal suture: between the frontal bone and the parietal bones
  • Lambdoid suture: between the occipital bone and the parietal bones

Mandible

• The only mobile bone of the skull
• Articulates with temporal bones in the temporomandibular joint (TMJ)

Hyoid Bone

• U-shaped bone located in the neck
• Consists of a body, greater and lesser horns
• Does not articulate with any bone and is suspended in place by membranes, muscles, and ligaments
• Important for movements of the tongue, pharynx, and larynx

Vertebral Column

• Divided into five groups:
  • Cervical (7)
  • Thoracic (12)
  • Lumbar (5)
  • Fused sacrum (5)
  • Fused coccygeal (4)
• Normal curves of the vertebral column:
  • Cervical curve
  • Thoracic curve
  • Lumbar curve
• Abnormal curvatures:
  • Kyphosis (hump back): increase in the thoracic curvature
  • Lordosis: increase in the lumber curvature
  • Scoliosis: abnormal lateral curvature of the vertebral column