Human Body Systems and Diseases Bone Tissues

Functions of Bones

Support, Protection, Structure, Movement, Mineral Storage, Blood Production

Compact Bone

Hard and compact with little space. Bone mineral arranged into tight circles called osteons. 80% of bone mass

Trabecular Bone

Porous, like a network. Allows blood vessels and bone marrow to easily fill it

Long Bones

Bones that are longer than they are wide, primarily made of compact bone. Ex. Leg and arm bones

Short Bone

Cube-shaped bones, with a thin layer of compact bone. Ex. wrist and ankle bones

Sesamoid Bones

Bones embedded in tendons. Ex. Patella

Flat Bones

Thin and curved bones with parallel layers of compact bone. Ex. Sternum and skull

Irregular Bones

Bones that don’t fit any other category

Collagen Fibers

Allows bones to endure stretching forces

Other Minerals

Allows bones to endure compression forces

Osteons

Their circular shape and layers give bones strength

Lamellae

Concentric rings of collagen fibers that make up the structural support of the bone. Connective tissue that surrounds the Central Canal

Central (Haversian) Canal

Tube-like passage in bone tissue. Contains the bone’s blood and nerve supply.

Canaliculi

Small channels that extend from the lacunae to the central canal. Provides passageways through the bone matrix

Osteocytes

Fully formed bone cells located in lacunae

Osteoblasts

bone forming cells that create new bone and help heal and grow existing bones

Osteoclast

bone cells that break down old or damaged bone tissue to make room for new bone growth

Lacunae

small hollow spaces within the bone matrix where osteocytes reside