Skeletal System: Bone Tissue Flashcards

Vocabulary flashcards for reviewing the skeletal system and bone tissue.

Diaphysis

Shaft of a long bone.

Epiphysis

One end of a long bone.

Metaphyses

Areas between the epiphysis and diaphysis, including the epiphyseal plate in growing bones.

Endosteum

Lines the marrow cavity.

Periosteum

Tough membrane covering bone but not the cartilage.

Osteogenic layer

Bone cells and blood vessels that nourish or help with repairs.

Histology of Bone

Widely spaced cells separated by matrix; a type of connective tissue.

Matrix of Bone

Inorganic salts, primarily hydroxyapatite and some calcium carbonate, and collagen fibers of bone.

Osteoprogenitor cells

Stem cells that can divide to replace themselves and become osteoblasts.

Osteoblasts

Cells that form matrix & collagen fibers but can’t divide.

Osteocytes

Mature bone cells that no longer secrete matrix.

Osteoclasts

Huge cells from fused monocytes (WBC) that function in bone resorption.

Compact Bone

Looks like a solid hard layer of bone; makes up the shaft of long bones and the external layer of all bones.

Spongy Bone

Does not contain osteons; consists of trabeculae surrounding many red marrow filled spaces.

Intramembranous ossification

Formation of bone directly from or within fibrous connective tissue membranes.

Endochondral ossification

Formation of bone from hyaline cartilage models.

Interstitial Growth

Growth of bone in length.

Appositional Growth

Growth in width.

Giantism

Oversecretion of hGH during childhood.

Closed fracture

No break in skin.

Open fracture

Skin broken.

Comminuted fracture

Broken ends of bones are fragmented.

Pott’s Fracture

Distal fibular fracture.

Colles’s Fracture

Distal radial fracture.

Stress fracture

Microscopic fissures from repeated strenuous activities.

PTH

Parathyroid hormone; secreted when Ca+2 levels fall.

Calcitonin

Hormone secreted from parafollicular cells in thyroid if Ca+2 blood levels get too high.

Demineralization

Loss of calcium and other minerals from bone matrix.

Osteoporosis

Decreased bone mass resulting in porous bones.

Rickets

Calcium salts are not deposited properly; bones of growing children are soft.

Osteomalacia

New adult bone produced during remodeling fails to ossify.