Case Study 04

Module 04 Case Study: Bone Tissue

Part I— “Marissa” Questions

1. Describe bone tissue and the role each component plays in bone physiology and remodeling. What is the difference between compact and spongy bone?

Orosseous tissue, is a hard, dense connective tissue that forms most of the adult skeleton. In the areas of the skeleton where bones move cartilage, a semi-rigid form of connective tissue which provide flexibility and smooth surfaces for movement. Compact bone is dense osseous tissue that can withstand compressive forces while spongy bone is trabeculated osseous tissue that supports shifts in weight distribution.

2. Explain the relationship between calcium and bones.

Calcium is the most abundant mineral in the human body. Calcium is need for mineralization, or tooth health, regulation of the heart rate and strength of contraction, blood coagulation, contraction of smooth and skeletal muscle cells, and regulation of nerve impulse conduction.

3. Explain how the body controls calcium levels in the bones and blood. Be sure to describe the roles of parathyroid hormone (PTH) and calcitonin in detail.

The body deposits calcium in the bones when blood levels get too high, and it releases calcium when blood levels drop too low. This process is regulated by PTH, vitamin D, and calcitonin. . When calcium is not binding to these

receptors, the cells release PTH, which stimulates osteoclast proliferation and resorption of bone by osteoclasts. PTH promotes reabsorption of calcium from the urine by the kidneys, so that the calcium returns to the blood and stimulates the synthesis of vitamin D.

4. Explain specifically how osteoporosis affects the bone matrix and the normal bone remodeling cycle.

When osteoporosis is present, the balance between this resorption and the other half of the cycle, bone formation, is not stable. This causes bone loss to occur.

5. Discuss what scientists know about the genetics behind osteoporosis....