It has more cells and the matrix is not lamellar.
An outer fibrous layer and an inner cellular layer containing osteoprogenitor cells.
Essential for calcium absorption and bone mineralization.
To resorb bone tissue by releasing protons and lysosomal hydrolases into the extracellular space.
Multinucleated cell known as osteoclasts.
Bone-lining cells, also known as endosteal cells.
Cylindrical units.
Lacunae (singular: lacuna).
Osteoblasts.
Volkmann canal.
Osteomalacia is a problem with bones not hardening due to impaired mineralization, while osteoporosis is the weakening of the bone resulting from low peak bone mass, increased bone resorption, and impaired bone formation.
The extracellular matrix of bone.
An immature (woven) bone with thick trabeculae lined by osteoblasts and endosteal cells.
Replacement of woven bone by the inner and outer layers of compact bone with spongy bone between them.
Howship’s lacuna.
They contain blood vessels and nerve fibers that nourish the bone cells.
Osteoblast, osteocyte, osteoprogenitor cells, bone lining cells, and osteoclast.
Unmineralized bone matrix, the osteoid.
They contain blood vessels and nerves for the osteons.
By gap junctions.
To maintain viability.
a. Relatively quiescent osteocyte - Few rER and mitochondria, fills the lacuna. b. Formative osteocyte - rER, golgi, osteoid in pericellular space, arrow nonmineralized osteoid. Outer margin of lacuna is not present. c. Resorptive osteocyte (osteocytic remodeling) - The pericellular space is devoid of collagen fibrils. Outer boundary of lacuna.
Osteocytes shrink and lacunae appear empty with a small nucleus attached to their walls.
As compact (dense) or spongy (cancellous).
Sponge-like meshwork consisting of trabeculae (spongy bone).
Endosteal cells.
To line bone cavities and contain osteoprogenitor cells.
It contains several osteons with concentric lamellae, Haversian canals with blood vessels, nerve, and connective tissue.
A bone cell, or osteocyte.
Large, multinucleated cells with acidophilic cytoplasm.
Hemopoietic progenitor cells in bone marrow.
Depositing bone, beginning at the origin of the resorption canal.
Progressive loss of normal bone density.
Rickets in children and osteomalacia in adults.
Osteoid, which contains collagen fibrils.
Trapped osteoblasts become osteocytes.
Bone resorption (eating bone).
Osteocytes.
Bones appear dense on X-ray, but they are very fragile and break easily.
Osteoid.
By gap junctions.
Channels in the bone that transmit blood vessels and communicate with the Haversian canals.
Type I collagen.
Mesenchyme (embryonic connective tissue).
Support, protection, regulation of blood calcium and phosphate levels.
In the fetal period.
Layers of bone tissue that line the medullary cavity.
By canaliculi.
Bone matrix proteins, which form osteoid.
Osteoid or bone matrix.
Volkmann's canal
Osteoid (uncalcified matrix).
Markedly basophilic.
Mesenchymal stem cells.
Osteons or Haversian systems.
Compact, dense layer (compact bone).
Bone resorption and remodeling.
No, osteoclasts do not have PTH receptors.
Osteons
Creation of a new osteon.
Bony canaliculi
Lacunae.
They fill the spaces between osteons in compact bone.
Type I collagen.
The 'closing end' of the BRU.
Lamellae
Longitudinal section of ground bone used for microscopic examination.
Bundle bone or woven bone.
Osteocytes.
They are the structural unit of compact bone, providing strength and support.
A shallow bay called a resorption bay (Howship’s lacuna).
Short and thick.
Haversian canal
An ossification center.
They exhibit a reduced zone of proliferation.
On the surface of bone where resorption is taking place.
Osteoclastic erosion of bone in a 'resorption canal'.
No, they are not surrounded by concentric lamellae.
Circumferential lamellae
Cross-section of bone from which the mineral content has been removed.
Intramembranous ossification and Endochondral ossification.
The vascular and nerve supply of the osteon.
During the fetal period.
Layers of bone tissue that line the outer surface of compact bone.
Their length is shortened.
A rare congenital disease characterized by increased bone density and defective osteoclast function.
Parathyroid hormone (PTH) secreted by the parathyroid glands.
Perforating (Volkmann’s) canals.
Cartilage cells undergo divisions and organize into distinct columns.
The hypertrophied cells begin to degenerate, and the cartilage matrix becomes calcified, serving as an initial scaffold for deposition of new bone.
Osteocytic remodeling.
1. Zone of reserve cartilage, 2. Zone of proliferation, 3. Zone of hypertrophy, 4. Zone of calcified cartilage, 5. Zone of resorption.
Osteocytes are embedded within the bone matrix and stained dark blue.
It refers to a cross-section of bone tissue after removal of calcium salts.
Osteoblasts are responsible for the calcification of bone matrix.
Interstitial lamellae
Mononuclear hemopoietic cells.
Lacunae
A two-stage process whereby cortical bone is remodeled from within.
Canaliculi.
Matrix metalloproteinases (MMPs).
To repair microdamages in the matrix.
<p>Imbalance between osteoclast-mediated bone resorption and osteoblast-mediated bone deposition. LACK OF ESTROGEN.</p>
