Cheat Sheet 18: Skeletal System

Axial skeleton

Basic framework including skull and vertebral column.

Appendicular skeleton

Bones of limbs and girdles, excluding axial.

Articular cartilage

Smooth tissue covering joint surfaces for movement.

Proximal epiphysis

End of long bone closest to the body.

Endoskeleton

Internal skeleton supported by soft tissue.

Cartilage

Avascular, flexible connective tissue in skeleton.

Bone

Hard, living connective tissue providing structure.

Spongy bone

Less dense bone with trabecular structure.

Metaphysis

Region between diaphysis and epiphysis in bones.

Epiphyseal line

Remnant of growth plate in mature bones.

Bone Function

Supports, protects, stores minerals, produces blood.

Red bone marrow

Site of blood cell production in bones.

Endosteum

Thin membrane lining the medullary cavity.

Compact bone

Dense bone providing strength and support.

Sutures

Immovable joints connecting skull bones.

Foramen

Opening in bone allowing nerve passage.

Medullary cavity

Hollow space in long bones containing marrow.

Diaphysis

Long shaft of a long bone.

Yellow bone marrow

Fat storage tissue in bone cavities.

Ligaments

Connect bone to bone, stabilizing joints.

Periosteum

Outer membrane covering bones, aiding growth.

Origin

Muscle attachment point on stationary bone.

Osteoprogenitor cells

Stem cells differentiating into bone-forming cells.

Osteocytes

Mature bone cells maintaining bone tissue.

Nutrient artery

Supplies blood to bone tissues.

Insertion

Muscle attachment point on moving bone.

Osteoblasts

Bone cells forming new bone matrix.

Osteoclasts

Cells resorbing bone matrix, releasing minerals.

Tendons

Connect muscle to bone, facilitating movement.

Flexion

Bending movement reducing joint angle.

Extension

Straightening movement increasing joint angle.

Long bone

Bone type with a shaft and two ends.

Osteon

Functional unit of compact bone structure.

Lacunae

Spaces housing osteocytes within bone.

Fibrous joint

Connects bones with dense connective tissue.

Epiphyseal plate

Cartilage layer for bone growth in children.

Volkmann's canals

Channels connecting Haversian canals in bone.

Haversian canals

Vertical channels for blood vessels in bone.

Trabeculae

Bony spicules forming spongy bone structure.

Synovial joint

Most common joint type allowing movement.