Bone: Structure and Function Flashcards
The composition of bone is similar to _____
Dentin
Composition of bone is _______ overlaid on a _________ scaffold
- Hydroxyapatite
2. Collagen I scaffold
What are the Non-collagenous proteins in bone?
- BSP
- OP
- OC
- ON
- Matrix Extracellular Phosphoglycoprotein
By percentage what is the composition of bone?
67% inorganic
33% organic
What makes up the inorganic portion of bone?
Hydroxyapatite
What makes up the Organic component of bone?
28% collagen
5% noncollagenous proteins
Name 3 physiological roles of bone
- Structural
- Calcium Homeostasis (9-10mg/DL)
- Reservoir for growth factors in tissue repair
Bone contains both ________ and _______ progenitor cell populations in marrow
- Hematopoietic
2. Mesenchymal
What is the basic macrostructure of bone?
Outer layer of dense compact/cortical bone with an inner cavity
What is contained within the inner cavity of bone?
Marrow and cancellous/trabecular bone
What colors is marrow?
Red or yellow
T/F Bone is highly vascular with a network of blood vessels
True
What are the 3 organizational units in the macrostructure of compact bone?
- Circumferential
- Concentric/osteonic lamellae
- Interstitial lamellae
What is circumferential compact bone?
Outer ring of bone tissue
What is Concentric/osteonic lamellae?
Intact osteons
What is the interstitial lamellae?
They fill the space between concentric lamellae; former concentric lamellae
What is the basic functional unit of compact bone?
Osteon
Osteons form cylinders that run in what orientation?
parallel to the long axis of a bone
Osteons are formed from ______
Concentric lamellae
What would you call a concentric ring of bone, built around a canal housing a capillary?
Osteon
What would we call the canal that runs in the osteon?
Haversian canals
What connects haversian canals and links osteons?
Volkmann canals
What do we call the spongy bone that is much less densely arranged than compact bone?
Cancellous bone
Where would you find cancellous bone?
- At the ends of long bones, in apposition to joints
2. Associated with the marrow spaces
What purpose does cancellous bone serve?
Provides structural support for marrow tissues, highly vascular
What type of bone is a site of blood cell production and supports mesenchymal and hematopoietic progenitor cell populations?
Cancellous bone
Define the periosteum
Connective Tissue layer attached to the outer surface of a bone by Sharpey’s fibers
What are the two layers of the periosteum?
- Outer fibrous layer
2. Inner layer in apposition to the bone surface
Which layer of the periosteum is both highl cellular and vascularized?
Inner layer
What is the Endosteum?
Loose Connective tissue covering the inner surface of both cancellous and compact bone
What separates the marrow from the bone and is poorly defined histologically?
Endosteum
What is the origin of Osteoblasts?
Mesenchyme
What would you call an encapsulated osteoblast?
Osteocyte
What is the origin of Osteoclasts?
Hematopoietic origin
Carefully regulated interaction between Osteoblasts, Osteocytes, and Osteoclasts is responsible for bone formation, repair, and maintenance T/F
True
What is the mononucleated cells that synthesize osteoid matrix?
Osteoblasts