Test 2: 38-40
Compiled By Simon Mwangi
Edition: 2024/25
, Science | Biochemistry I of XIV pages
1. mineral is deposited in the form of ___. Found in ___, ___ and ___
hydroxyapatitebone, hypertrophic cartilage and teeth.
Needs permissive environment and lack of inhibitors
2. mineral deposition is dependent on ___ and ___
permissive environment and lack of inhibitors
3. Most calcium (>99%) and phosphate (~80%) ions of the body are stored in ___; ~1% exists in the serum
plasma). Total serum calcium concentration is 10 mg/dl, or 2.5 mM. About ~50% of the serum calcium is
bonefree calcium
4. Most ___ (>99%) and ___(~80%) ions of the body are stored in bone.
calcium and phosphate
5. Serum calcium is under close ____, and is regulated on a minute-to-minute basis.
homeostatic control
6. Even though there is enough calcium and phosphate present, spontaneously depositing mineral doesnt occur
1) inhibitors are present that prevent mineralization2) a permissive environment is required (such as in bone,
7. The mineral phase of cartilage, bone, and teeth is a calcium/phosphate precipitate inthe form of ____
hydroxyapatite.
8. ___ particles are very small (microcrystalline), very reactive, highly insoluble, and able to bind many other
hydroxyapatite
9. A ____ or template (provided by matrix vesicles in cartilage and hole zones of type I collagen in bone) is
for initial crystal formation. The first mineral deposited is a poorly organized apatite which gradually becomes
nucleation sitehydroxyapatite
10. Cartilage is not vascularized, and does not mineralize. However, during ____, hypertrophic cartilage
endochondral ossification
11. During endochondral ossification, hypertrophic cartilage acquires the ability to mineralize and to be
collagen type 2, 9 and 11Collagen type 10
12. Late hypertrophic chondrocytes release ___ (MVs) from their plasma membrane into the ECM.
matrix vesicles
13. matrix vesicles provide nucleation sites where ____ first occurs.
mineralization
14. Mineralization is accomplished by concentrating calcium and phosphate ions in the ___, and permitting
crystals to form within the MV membrane. As crystals grow, the MV membrane ruptures and mineral is
matrix vesicles
15. explain Matrix vesicles
Biochemistry 2024/25 Edition