Welcome to the Bone Zone

1. How many types of bones are there?
4. Hydroxyapatite stores 99% of the body’s ________.
5. Support, protection and movement are all ____________ roles of the skeleton.
7. Bone cells only account for ____ per cent of bone mass.
9. These cells create bone matrix.
10. The process of ossification that results in most bone formation, including long bones and involves secondary ossification centres.
12. Another name for trabecular bone.
13. Fluid held under pressure in a closed, semi-rigid, body compartment
14. This condition involves the breakdown of bone occurs more than laying down of new bone matrix, resulting in compromised bone tissue.
18. Nutrient store and blood cell formation (a.k.a. hematopoiesis) are ____________ roles of the skeleton.
19. Number of bones in the axial skeleton

2. The circular column unit of bone also known as the Haversian system that makes up the compact bone tissue, and it contains osteocytes in lacunae, canaliculi and layers of lamellae surrounding a central canal that hold blood vessels.
3. During bone remodelling, osteoclasts breakdown bone on the outside of the _________ funnel.
6. The process of ___________ ossification results in primarily flat bone formation and is formed from mesenchyme tissue.
8. Also known as primary bone, in ______ bone the collagen fibres in the tissues are disorganised. Its the first bone tissue laid down after initial foetal bone development and repair after fractures.
9. This is the precursor for bone and is secreted by osteoblasts.
11. The end of the bone that initially grows separately from the shaft during development.
15. _______ osteons have lamellae that merge smoothly with surrounding bone and can be replaced by secondary osteons.
16. The bone _________ unit involves approximately 10 osteoclasts digging out a tunnel parallel through the bone shaft while osteoblasts (~100) lay down new bone within the tunnel which can results in secondary osteon formation.
17. Material that comprises 33% of bone tissue