Bone Structure and Cells Lecture Review

Flashcards covering key vocabulary related to bone structure, bone cells, and the process of ossification from the lecture notes.

Holes (in bone)

Openings in the bone that allow things to pass through them.

Foramen

A small hole in bone that blood vessels and nerves pass through.

Canals (bone marking)

Openings in bone that can range in size, like the vertebral canal for the spinal cord.

Meatus

A specific type of bone opening, such as the auditory meatus at the entrance of the ear canal.

Sinuses (bone marking)

Large regions of empty space on the bone where extra tissue gets attached, not strictly holes.

Depressions (bone marking)

Markings on bone that often serve as attachment points for muscles or ligaments.

Iliac crest

A major attachment point for muscle on the pelvis.

Lacrimal canal

The tear duct canal.

Fissures (bone marking)

Elongated, slit-like openings in bone that allow the passage of nerves, such as optic nerves.

Osseous tissue

Bone tissue, consisting of a handful of cells entrenched in a dense collagen fiber matrix with minerals deposited.

Collagen

The main structural component of bone.

Hydroxyapatite

The major mineral deposited in bones, a composite of calcium phosphate and calcium carbonate.

Osteocytes

Mature bone cells found in lacunae within the fibrous, mineralized matrix of bone, performing routine maintenance.

Lacunae

Little holes or cavities within the bone matrix where osteocytes are housed.

Osteogenic cells

Stem cells of bone that can differentiate into various bone cell types, primarily osteoblasts.

Osteoblasts

Cells that build up bone by attracting and depositing minerals onto collagen fibers around them.

Osteoclast

A macrophage derived from the immune system, whose function is to break down old or damaged bone and recycle nutrients.

Bone remodeling

The continuous process of bone breakdown by osteoclasts and rebuilding by osteoblasts.

Resorption

The process of drawing mineral back out of bone, specifically calcium and phosphorus.

Osteoporosis

A condition resulting from osteoclasts being significantly more active than osteoblasts, leading to hollowness and fragility in bones.

Compact bone

Dense and sturdy bone found in the diaphysis, providing primary support and structured into osteons.

Osteon

The structural unit of compact bone, resembling tree rings around a central canal.

Central canals (Haversian canals)

Canals within osteons that carry blood vessels and nerves into the bones, supplying nutrients.

Lamella

The bony matrix found between osteocytes within an osteon, where collagen and minerals are deposited.

Canaliculi

Microscopic small canals that run between osteocytes, connecting them and allowing for communication.

Spongy bone (Cancellous bone)

A type of bone with a less ordered, branched lattice-like structure compared to compact bone, typically found at the ends of long bones.

Trabeculae

The functional units of spongy bone, appearing as a network of branches that form a lattice.

Nutrient canals

Specific channels through the periosteum that allow blood vessels to enter and supply nutrients to the bone.

Ossification (Osteogenesis)

The process of bone formation, beginning around three months into embryonic development.

Cartilaginous prototype

A template of a skeleton made entirely of cartilage that forms in an embryo before bone development.

Mineralization (bone)

The process of depositing minerals onto the collagen matrix of bone, which continues into adulthood (around 25-26 years old).

Mesenchymal tissues

Undifferentiated connective tissue that can develop into various other tissues, including bone.

Intramembranous ossification

A specific type of ossification where bone develops directly from mesenchymal tissue without a cartilage template, seen in early embryonic development.

Ossification centers

Areas where mesenchymal cells differentiate into osteoblasts and begin producing osteoid during intramembranous ossification.

Osteoid

Unmineralized bone matrix, consisting of collagen fibers and materials that attract minerals, essentially pre-mineralized bone.