Study Slides Chapter 7

Red bone marrow

Site of hemopoiesis; produces all blood cell types.

Yellow bone marrow

Site of lipid storage in bone; serves as an energy reserve.

Bone Functions

Provides structural support, organ protection, and mineral storage.

Sutures

Immovable fibrous joints; connects skull bones together.

Foramen

Provides passageway for blood vessels and nerves.

Fontanelle

Flexible connective tissue; allows infant skull compression and brain growth.

Bone Storage

Mineral reservoir; maintains levels of Calcium, Phosphate, and Lipids.

Osteoprogenitor

Bone stem cell; divides to produce new osteoblasts.

Osteoblasts

Secretes osteoid and initiates calcification.

Osteoclasts

Dissolves matrix to release calcium into blood.

Osteocytes

Mature bone cell; monitors stress and maintains matrix in lacunae.

Appositional Growth

Bone growth in diameter; adds new bone tissue at the surface.

Interstitial Growth

Growth in length; occurs via cartilage division at epiphyseal plate.

Calcium & Minerals

Inorganic components; provide hardness and compression resistance.

Hormones (General)

Chemical messengers; coordinate bone remodeling and calcium levels.

Gravity

Physical force; stimulates osteoblasts to increase bone density.

Mechanical stress

Physical loading; triggers remodeling to strengthen bone in high-use areas.

Compact bone

Also called cortical or dense bone; provides strength and weight-bearing support.

Spongy bone

Also called trabecular or cancellous bone; lightens the skeleton and houses marrow.

Intramembranous Ossification

Forms flat bones from mesenchymal membranes.

Endochondral Ossification

Replaces a hyaline cartilage model with bone in utero.

Vitamin D Conversion (Skin)

Synthesis stage; produces Vitamin D3 via UV light.

Vitamin D Conversion (Liver)

Intermediate stage; converts Vitamin D3 into Calcidiol.

Vitamin D Conversion (Kidney)

Activation stage; converts Calcidiol into active Calcitriol.

PTH (Parathyroid Hormone)

Increases blood calcium by activating osteoclasts.

Calcitonin

Decreases blood calcium by inhibiting osteoclasts.

Growth hormone

Stimulates cartilage growth at the epiphyseal plate.

Hematoma formation

Repair Stage 1; forms a blood clot to bridge the fracture.

Fibrocartilaginous callus

Repair Stage 2; forms a soft collagen/cartilage bridge.

Bony callus

Repair Stage 3; replaces soft callus with hard spongy bone.

Bone remodeled

Repair Stage 4; replaces spongy bone with compact bone.

Paranasal sinuses

Mucosa-lined cavities; lighten the skull and provide voice resonance.

Calcitrol

Absorbs calcium from food into bloodstream in the small intestine.