Part 1 - Unit 3: Skeletal System

Functions of Skeletal System:

Support and protection

Functions of Skeletal System: Body movement - muscles “pull” on _____

bones

Functions of Skeletal System: Hematopoiesis

Blood cell formation

Functions of Skeletal System: Storage of _____ materials

inorganic; calcium, sodium, potassium

2 main divisions of skeletal system

Axial and Appendicular

Components of the Axial Skeleton

head, neck, trunk; skull Hyoid bone, vertebral column, ribcage, sternum

Appendicular Skeleton

Limbs and bones connecting the limbs to the pectoral girdle and pelvic girdle

Pectoral Girdle

Scapula, clavicle, arms

Pelvic Girdle

Coxal bones, legs

Epiphysis

Ends of Bone

Spongy Bone

Red Marrow

Diaphysis

Shaft of Bone

Articular Cartilage

Padding, ends of bone

Periosteum

Membrane that covers entire bone

Medullary Cavity

Contains Yellow Marrow

Compact Bone

Wall of diaphysis

Spongy Bone

Cancellous, epiphysis

Proximal Epiphysis

The epiphysis closest to the body’s center

Distal Epiphysis

The epiphysis that is farthest away to the body’s center

Flat Bone

Function(s)

Protection

Examples

Sternum, ribs, skull

Long Bone

Function(s)

Support weight, movement

Examples

Femur, tibia, fibula, humerus, radius, ulna

Short Bone

Function(s)

Stability, movement

Examples

Carpals, tarsals

Irregular Bones

Function(s)

Protect Organs

Examples

Vertebrae, Pelvis

Sesamoid Bones

Function(s)

Reinforce tendons

Examples

Patella (Kneecap)

Endosteum

Lines of the medullary cavity

Red Marrow

Produces Blood

Yellow Marrow

Fat storage

Another name for bone tissue

Osseous tissue

The matrix

composed of collagen and inorganic materials like calcium and phosphate.

Collagen

A type of connective tissue found inside bone tissue

Osteocytes

Mature bone cells, enclosed in tiny chambers called lacunae

• These form rings called lamellae around Haversian canal which house blood vessels

Canaliculi

Tiny canals that link osteocytes

Osteon

Structural and functional unit of compact bone in humans and many other vertebrates

Ossification

A process in which bones initially form as hyaline cartilage, then gradually change into bone tissue

Primary Ossification

Increases bone diameter

Secondary Ossification

Increases bone length

Osteoblasts

Create Osteocytes

Osteoclasts

Bone resorption; break down and dissolve old, micro-damaged, or unneeded bone tissue.

Epiphyseal Disk

(Growth plate) is a band of cartilage between the epiphysis and diaphysis