Chapter 8. Bone

This chapter should help the student to:

• Describe bone as a connective tissue in terms of its cells, fibers, and ground substance.
• Compare bone cell types in terms of their origin, structure, and primary functions.
• Relate the physical properties of bone tissue to specific tissue components.
• List the bone tissue types and name the sites where each may be found.
• Compare the two processes of bone histogenesis in terms of embryonic tissue of origin, intermediate steps, structure of the mature tissue, and location in the body.
• Compare the steps of bone histogenesis with those of fracture repair.
• Know the alterations in tissue structure that occur during bone growth and remodeling.
• Explain the effects of nutrients and hormones on bone tissue structure and function.
• Identify bone types, cell types, and named structures in micrographs of bone tissue.
• List the types of joints and compare them in terms of their structure, mobility, and location.

1. List the functions of bone (I.B).

2. Describe two methods of preparing bone for microscopy that are necessitated by its hardness (III.A). Which method resembles a step in bone resorption (III.A.1.d. and D.1.a)?

3. List the functions of osteoblasts and the organelle(s) associated with each function (III.A.1.b).

4. Describe osteoblast cytoplasmic staining and name the cell components stained (III.A.1.b).

5. Describe the relationships among osteoprogenitor cells, osteoblasts, and osteocytes (III.A.1.a–c).

6. Compare osteocytes (III.A.1.c) with osteoblasts (III.A.1.b) in terms of their shape, filopodia, amount of RER, location, and rate of matrix synthesis.

7. How can osteocytes located far from capillaries survive when nutrients, oxygen, and wastes cannot diffuse through calcified bone matrix (III.A.1.c)?

8. Describe osteoclasts (III.A.1.d) in terms of:

1. Size

2. Number of nuclei

3. Precursor cells

4. Staining properties

5. Organelles present

6. Major function

7. Substances secreted

8. Location and function of ruffled border

9. Reaction to parathyroid hormone

10. Reaction to calcitonin

9. List the inorganic components of bone matrix. Which two are most abundant (III.A.2.b)?

10. Describe the composition of the organic matter (osteoid) of bone matrix (III.A.2.a.[1] and [2]).

11. Compare endosteum and periosteum in terms of location, thickness, number of layers, and cell types present (II.B).

12. Compare compact and spongy bone in terms of the presence of cavities and trabeculae, histologic structure under high-power magnification, and location (III.B.1 and 2).

13. Compare primary and secondary bone (III.C.1 and 2) in terms of:

1. Relative permanence

2. Type prevalent in adults

3. Orientation of collagen fibers

4. Cellularity (cell-to-matrix ratio)

5. Presence of lamellae

6. Relative mineral content

14. Sketch an osteon (haversian system) in cross-section (III.C.2.b; Fig. 8–1) and label the following:

1. Haversian canal

2. Endosteum

3. Blood vessel

4. Nerve

5. Lymphatic vessel

6. Lamellae

7. Lacunae

8. Osteocytes

9. Filopodia

10. Canaliculi

15. Compare haversian and Volkmann's canals in terms ...