Bone Flashcards
Pressure applied to bone induces what type of remodeling?
Resorption
Tension applied to bone induces what type of remodeling?
Deposition
What are the epiphyses?
Ends of bones
What are the metaphyses?
Angulation between epiphysis and diaphysis
What are the diaphyses?
Shaft of bone
What is the periosteum?
External connective tissue capsule of bone
What layers are present in active (growing) periosteum?
- Outer fibrous layer
2. Inner cellular layer
What layers are present in inactive (mature) periosteum?
Only well-developed outer fibrous layer
How is the fibrous layer of periosteum anchored to the bone?
Sharpey’s fibers
What are Sharpey’s fibers?
Bundles of collagenous fibers; anchor fibrous periosteum to bone
In the inner cellular layer of periosteum, what cells are present in a growing bone?
Osteoprogenitor cells
In the inner cellular layer of periosteum, what cells are present in a non-growing bone?
Periosteal cells
Does periosteum cover the bone at articular surfaces?
No
Does periosteum cover the bone where tendons attach?
No
What is the endosteum?
Internal connective tissue capsule of bone
What makes up the endosteum?
Thin layer with single row of osteoprogenitor cells
Endosteum lines what compartments within bone?
- Bone marrow cavity
- Haversian and Volkman canals
- Spicules and trabeculae
What gives bones their hardness?
Inorganic minerals
What are the inorganic components of bone?
- Hydroxyapatite crystals (calcium phosphate)
2. Bicarbonate, citrate, magnesium, sodium, potassium
What makes up the organic component of bone?
- Fibers
2. Ground substance
What is the function of the organic component of bone?
Prevents brittleness
What is the main type of collagen in the organic component of bone?
Type I
What are the components of the ground substance in bone?
- Proteoglycans
- Multiadhesive glycoproteins
- Bone-specific, Vitamin K dependent proteins
- Growth factors and cytokines
What is the function of proteoglycan side chains in the ground substance of bone?
Binding growth factors
What binds growth factors in the ground substance of bone?
Proteoglycan side chains
What are the multiadhesive glycoproteins in the ground substance of bone?
- Osteonectin
2. Sialoproteins
What is the function of osteonectin?
Serves as glue between collagen and hydroxyapatite crystals
What serves as glue between collagen and hydroxyapatite crystals?
Osteonectin
What are the sialoproteins?
- Osteopontin
2. Sialoproteins I and II
What is the function of osteopontin?
Binds cells to bone matrix
What binds cells to bone matrix?
Osteopontin
What are the functions of sialoproteins I and II?
- Bind cells to bone matrix
2. Begins calcium phosphate formation during mineralization
What is an example of a bone-specific, Vitamin K dependent protein?
Osteocalcin