Cartilage and bone

Classification of cartilage

Hyaline
Elastic
Fibrocartilage

Histiogenesis

Creation of tissue

Types of histiogenesis

Appositional growth
Interstitial growth

Hyaline cartilage: extracellular matrix

Glossy, homogeneous, amorphous;
Collagen, ground substance

Hyaline cartilage cells

chondrocytes, lacunae

In Hematoxylin and eosin staining, chondrocytes are often

Poorly preserved and appear as a nucleus in a lacuna

Hyaline cartilage is

Initial skeleton of fetus;
Precursor to many developing bones through process of endochondral ossification

hyaline cartilage function

Epiphyseal growth plate during bone development; support

where hyaline cartilage is found

Articulate surface of adult long bones, respiratory tract

endrochondral ossification

process of forming bone from cartilage

Chondro

Cartilage

Osteo

Bone

Elastic cartilage

Matrix has elastin fibers with collagen and ground substance, Does not calcify, provides flexibility

elastic cartilage location

External ear, external auditory canal, Eustachian tube, larynx

Fibrocartilage is

Strongest cartilage

Fibrocartilage is present in

Intervertebral discs, symphysis pubis, menisci of knee joints, where tendon attaches to bone

Presence of Fibrocartilage indicates

Resistance to compression is required

Appositional growth

Formation of cartilage on the surface of preexisting cartilage

Interstitial growth

Growth from within cartilage mass, chondrocytes still capable of cell division, matrix is distensible

Feature that distinguishes bone from other connective tissues

Calcification of extracellular matrix

Calcium can be

Mobilized and taken by blood as needed to maintain appropriate levels in other tissues

bone matrix components

Collagen, ground substance; both are calcified

Osteocytes

Found in lacunae, possess canulaiculi

Canaliculi

Small tunnels extending into the matrix

Osteoblasts

Bone-forming cells present on the surface of developing bone; once it surrounds itself with matrix it is an osteocyte

Osteoclasts

Bone-reabsorbing cells found on bone surfaces during early stages of remodeling

Long bones

Shaft, two ends, compact bone in middle; ends are epiphysis; middle is diaphysis

Short bones

Nearly equal in length, depth, width

Flat bones

Thin, plate like

Irregular bones

Irregular bones

External bone surfaces: Articular surface

Bone to bone contact; covered with hyaline cartilage

External bone surfaces: periosteum

Membrane of dense connective tissue; contains osteoblasts

Bone surfaces: bone cavities: endosteum

Often only one cell thick; contains osteoblasts and osteoclasts

Bone cavities

Bone marrow

compact bone: Haversian system

Concentric lamellar, Haversian canals

Haversian canals

Connect canaliculi and blood vessels

Compact bone: volkmann's canal

Connects Haversian canals, no concentric lamellae

The most common break in the femur

Is the head

spongy bone

Calcified tissue arranged as trabecula; empty space between trabeculae occupy considerable volume; intact living bone, regions between trabeculae filled with bone marrow

Endochondral ossification

A cartilage model serves as a precursor; bones of extremities; weight-bearing bones

Intramembraneous ossification

No cartilage model; flat bones of skulls and face, mandible, clavicle