BIOL1023 Exam 2 Review: Bone Tissue, Axial Skeleton, and Joints

Practice vocabulary flashcards covering key terms and concepts for bone tissue, bone growth and regulation, and joint classifications from the BIOL1023 Exam 2 Review Sheet.

Medullary (marrow) cavity

A space within the diaphysis that contains yellow bone marrow and blood vessels.

Yellow bone marrow

Consists of adipose cells that store triglycerides (fats).

Red bone marrow

A connective tissue that produces red blood cells, white blood cells, and platelets.

Articular cartilage

A thin layer of hyaline cartilage covering the ends of bones where they form a joint.

Epiphyses

Proximal and distal ends of bones.

Diaphysis (body or shaft)

The long, cylindrical main portion of the bone.

Metaphysis

In a growing bone, the region that contains the epiphyseal plate.

Periosteum

The tough covering that surrounds the bone surface wherever cartilage is NOT present.

Epiphyseal (growth) plate

A layer of hyaline cartilage in the area between the diaphysis and epiphysis of a growing bone.

Endosteum

A thin membrane lining the medullary cavity and internal spaces of spongy bone.

Epiphyseal line

A remnant of the active epiphyseal plate; a sign that the bone has stopped growing in length.

Bone lacunae

Small spaces between bone lamellae that contain osteocytes.

Osteoblasts

Immature bone cells that secrete the components required to build the extracellular matrix (ECM) of bone tissue.

Osteon (haversian system)

Structural unit of compact bone tissue.

Bone canaliculi

Interconnected, tiny canals filled with extracellular fluid (ECF); connect bone lacunae with one another and with the osteonic canals.

Osteonic (haversian or central) canals

Canals that run longitudinally in the center of an osteon; contain blood vessels and nerves.

Osteoclasts

Bone cells derived from monocytes; involved in bone resorption.

Bone trabeculae

Irregular pattern of thin columns of bone lamellae found in spongy bone tissue.

Osteocytes

Mature bone cells that maintain the daily activities of bone tissue.

Osteoprogenitor cells

Unspecialized bone stem cells derived from mesenchyme.

Endochondral ossification

The formation of bone from hyaline cartilage.

Zone of hypertrophic cartilage

A column-like layer of large, maturing chondrocytes.

Zone of resting cartilage

A layer of small, scattered chondrocytes anchoring the epiphyseal (growth) plate to the epiphysis.

Zone of proliferating cartilage

A layer of actively dividing chondrocytes.

Zone of calcified cartilage

A layer of mostly dead chondrocytes.

Parathyroid hormone (PTH)

Raises blood calcium levels by increasing bone resorption.

Calcitonin (CT)

Decreases blood calcium levels by inhibiting osteoclasts.

Calcitriol

Active form of vitamin D; raises blood calcium levels by increasing absorption of calcium from the digestive canal (gastrointestinal tract) into the blood.

Insulin-like growth factors (IGFs)

During childhood, promotes bone growth by stimulating osteoblasts and by increasing synthesis of proteins needed to build new bone; secreted on stimulation by growth hormone (GH).

Sex hormones (estrogens and androgens)

Involved in bone growth by stimulating osteoblasts; shut down growth at the epiphyseal (growth) plates, causing lengthwise growth of bone to end.

Vitamin C

Nutrient needed for collagen synthesis.

Vitamins K and B12

Nutrients needed for synthesis of bone proteins.

Joint

A point of contact between two bones, between bone and cartilage, or between bone and teeth.

Suture

A fibrous joint that unites the bones of the skull.

Interosseous ligament

A fibrous joint where a bundle of dense irregular connective tissue binds bones.

Interosseous membrane

A fibrous joint where a substantial sheet of dense irregular connective tissue binds neighboring long bones.

Gomphosis

A fibrous joint where a cone-shaped peg fits into a cavity with a small amount of dense irregular connective tissue.

Epiphyseal cartilage

A type of synchondrosis that is a hyaline cartilage growth center during endochondral ossification; NOT a joint associated with movements.

Symphysis

A cartilaginous joint where the ends of the articulating bones are covered with hyaline cartilage, but a broad, flat disc of fibrous cartilage connects the bones.

Synchondrosis

A cartilaginous joint where the connecting material is a solid piece of hyaline cartilage.