Skeletal Tissue

Support

The skeletal system provides structural support for the body.

Protection

The skeletal system protects vital organs from injury.

Movement

The skeletal system facilitates movement by serving as attachment points for muscles.

Storage

The skeletal system stores minerals such as calcium and phosphorus.

Blood cell production

The skeletal system is involved in the production of blood cells.

Bone

A rigid organ that forms the skeleton and supports the body.

Cartilage

A flexible connective tissue; includes three types:hyaline, fibrocartilage, and elastic.

Hyaline cartilage

The most common type of cartilage, found at the ends of bones and providing a smooth joint surface.

Fibrocartilage

A type of cartilage that resists mechanical loads.

Elastic cartilage

A type of cartilage that can bend and recoil.

Tendons

Connective tissues that attach muscles to bones.

Ligaments

Connective tissues that connect bones to other bones.

Bone matrix

The extracellular material of bone, consisting of organic and inorganic components.

Organic matrix

Composed of collagen and proteoglycans, it is dynamic and alive.

Inorganic matrix

Composed of hydroxyapatite crystals (calcium phosphate).

Osteoblasts

Bone cells responsible for the formation of bone through ossification.

Ossification

The process of bone formation by osteoblasts.

Osteogenic cells

Precursor cells that develop into osteoblasts.

Osteocytes

Mature bone cells housed in lacunae, maintaining bone tissue.

Lacunae

Small spaces in bone matrix that contain osteocytes.

Canaliculi

Tiny canals that allow communication between osteocytes.

Osteoclasts

Bone cells responsible for the resorption and destruction of bone tissue.

Intramembranous ossification

The process of converting woven bone into lamellar bone.

Woven bone

A type of bone with collagen fibers arranged randomly.

Lamellar bone

A type of bone with collagen fibers oriented in one direction, providing strength.

Spongy bone

Bone with a porous structure, containing trabeculae and filled with marrow.

Trabeculae

Interconnecting rods or plates of bone found in spongy bone.

Red marrow

Bone marrow responsible for the production of blood cells.

Yellow marrow

Bone marrow primarily composed of fat, found in the diaphysis of long bones.

Compact bone

Dense bone structure containing osteons (Haversian systems).

Osteons

Structural units of compact bone, consisting of a central canal surrounded by concentric lamellae.

Diaphysis

The elongated cylindrical shaft of a long bone, containing yellow bone marrow.

Epiphysis

The enlarged ends of long bones that strengthen joints and serve as attachment sites for tendons and ligaments.

Metaphysis

The region between the diaphysis and epiphysis, containing the epiphyseal plate.

Articular cartilage

A thin layer of hyaline cartilage covering the epiphysis, reducing friction in joints.

Medullary cavity

The hollow space within the diaphysis that contains yellow bone marrow.

Endochondral ossification

The process of bone formation from cartilage, occurring during fetal development.

Interstitial growth

Growth in length of long bones occurring at the epiphyseal plate.

Appositional growth

Growth in diameter of bones occurring at the periosteum.

Factors affecting bone growth

Nutrition, vitamin D, vitamin C, and hormones play crucial roles in bone development.

Rickets

A condition caused by a lack of vitamin D during childhood, leading to weak bones.

Osteomalacia

A condition caused by a lack of vitamin D during adulthood, resulting in soft bones.

Chondroblasts

Cells that produce the matrix of cartilage.

Chondrocytes

Mature cartilage cells that are surrounded by the matrix.

Perichondrium

A double-layered connective tissue sheath covering cartilage, except at joints.

Appositional growth (cartilage)

Growth that occurs by adding new cells at the periphery of cartilage.

Interstitial growth (cartilage)

Growth that occurs by cell division and matrix addition between existing cells.