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Bone: Test Your Understanding
Teacher's Guide
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ward
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science
1. What are the two types of skeletal bones? Give an example of each.
The two types of skeletal bones are flat bones and long bones. The ribs are flat bones and the
femur is a long bone.
2. Compare and contrast osteoblasts and osteoclasts.
Osteoblasts and osteoclasts are alike in that they are both types of bone cells and they both remodel
bone. Also, activities of both types of bone cells are directed by hormones and other molecules that
circulate in the blood as well as regulators that are produced locally in the bone. Osteoblasts and
osteoclasts differ in their roles in remodeling bone. Osteoblasts are bone-forming cells that build
new bone. Osteoclasts are bone-resorbing cells that remove bone.
3. How are osteocytes thought to be involved in bone formation?
Osteocytes sense stresses and loads placed on the bone and convey this information to the osteoblasts
on the bone surface, thereby enabling bone to adapt to altered mechanical loading by the formation
of new bone. Osteocytes are also thought to be the cells that detect and direct the repair of microscopic
damage that frequently occurs in the bone matrix due to wear and tear of the skeleton.
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