Skeletal Tissue

Question 1

1. Describe the basic characteristics of cartilage.

Answer 1

1. Not vascular chondrocytes for cells intercellular matrix comprised of fibers and ground substance (mucopolysaccharide).

Question 2

2. Identify describe and give an example of the 3 basic cartilage types.

Answer 2

2. Hyaline cartilage is very glossy and the most common type of cartilage. The cells are numerous in their lacunae and the collagen fibers are evenly spaced for the smooth look. It can be found at the tip of your nose and capping bones at synovial joints. Fibrocartilage has strong bundles of collagen fibers making it rough looking and very strong. Fibrocartilage can be found at the pubic symphsis and in intervertebral discs. Elastic cartilage such as in your outer ear has elastic stretchy fibers.

Question 3

3. Describe the composition of bone.

Answer 3

3. Minerals (hydroxyapatite crystals - primarily calcium based for hardness) collagen fibers for strength and bone cells in their lacunae.

Question 4

4. Define osteocyte osteoblast and osteoclast.

Answer 4

4. Osteocyte is a mature bone cell. Osteoblast is a bone forming cell and is abundant on the periosteum. Osteoclast is a bone destroying cell and is abundant at the endosteum.

Question 5

5. List and describe the 7 parts of a typical long bone.

Answer 5

5. Articular cartilage epiphysis (ends) metaphysis (neck) diaphysis (shaft) marrow cavity periosteum (outer covering) endosteum (lining marrow cavity).

Question 6

6. Name the 2 types of bone according to the amount of interosseous space. Describe the features of the osteon.

Answer 6

6. Compact bone has little interosseous space and is characterized by long cylinders called osteons. Osteons have central (Haversian) canals filled with blood vessels as well as perforating canals connecting to the central canals. It has osteocytes and the matrix is arranged in concentric circles called lamellae which resemble tree rings in cross section. The kind of bone with a lot of interosseous space is spongy or cancellous bone. This bone has little spicules (trabeculae) of bone with space available for red bone marrow and blood cell production.

Question 7

7. Describe the 2 methods of ossification.

Answer 7

7. Endochondral ossification occurs with cartilage forming first followed by the cartilage turning to bone. Intramembranous or direct ossification occurs by the osteoblasts directly making the bone with no cartilage intermediate.

Question 8

8. Explain how bones increase in diameter.

Answer 8

8. Osteoblasts on the periosteum make more bone while the osteoclasts on the endosteum enlarge the marrow cavity.

Question 9

9. Name the 4 main classifications of bones according to their shape. Give an example of each.

Answer 9

9. Long - femur; Short - carpal; Irregular - vertebra Flat - sternum. A miscellaneous category is the sesamoid bone embedded in a tendon. The largest sesamoid bone is the patella.

Question 10

10. Describe the various markings of the surface of bone (e.g. fissure facet foramen meatus fossa condyle).

Answer 10

10. Fissure is a slit-like opening; facet is a flat articular surface such as those on the vertebrae foramen is a hole for nerves or blood vessels meatus is a canal a fossa is a depression a condyle is a smooth usually rounded articular surface.

Question 11

11. How many bones are there in an adult human skeleton?

Answer 11

11. 206

Question 12

12. Name the 2 main divisions of the human skeleton and the number of bones in each division.

Answer 12

12. Axial - 80; Appendicular - 126

Question 13

13. List the overall functions of the skeletal system.

Answer 13

13. Support movement protection blood cell production mineral storage