Module 5 Case Study

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? (2 points)

* Bone tissue is a type of connective tissue and is metabolic. The extracellular matrix is composed of calcium phosphate salt and collagen fibers which is continually remodeling itself and reacting with other tissues.

* Compact bone the matrix is arranged in concentric rings of calcified matrix. Make the characteristic very dense and hard.

* Spongy bone the matrix is arranged in structures that are thin spindles of bone matrix and bone cells, called trabeculae. Red bone marrow is located in spongy bone and produces blood cells.

2. Explain the relationship between calcium and bones. (1 point)

* Calcium is a main component is the matrix of bone tissue. It is a factor in helping bones achieve the density they needs for structure and strength.

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. (2 points)

* Calcitonin and the parathyroid hormone regulate blood calcium levels in the body.

* Calcitonin is secreted by the thyroid and will decrease blood calcium levels by stimulating increased activity of osteoblasts and decrease activity of osteoclasts. Also decreases the absorption of calcium in digestive tract and increase loss of calcium through kidneys.

* Parathyroid Hormone (PTH) is secreted by parathyroid gland and increases blood calcium levels by stimulating increase activity of osteoclasts and decrease activity of osteoblasts. Also increasing vitamin D production increasing absorption of calcium through intestinal tract and decreasing the loss of calcium through kidneys.

4. Explain specifically how osteoporosis affects the bone matrix and the normal bone remodeling cycle. (1 point)

* Changes in the...