Case Study 2 Bone Tissue

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) There are four types of bone tissue osteoblast, osteocyte, osteoclast, and osteogenic cell. Osteoblast are responsible for new bone formation and forms in the bone matrix. Osteocyte maintains bone tissue and maintain mineral concentration of the bone matrix. Osteogenic cells are undifferentiated and have a high mitotic activity that develop into osteoblast. Osteoclast are responsible for bone reabsorption.

There are two types of bone, compact and spongy. Compact bone provide structure and support to the long bones. Each compact bone has an osteon that is composed of lamella. Running down the center of the osteon is the central canal that has blood vessels, nerves, and lymphatic vessels that branch off into right angles at the perforating canal to extend to the periosteum and endosteum. Canaliculi connect with the lamella and eventually the central canal to allow nutrients to be transported to osteocytes and waste to be removed from them. Spongy bone consist of trabeculae that contain lamella, osteocytes, lacunae, and canaliculi. The trabeculae is sometimes filled with red bone marrow. Blood vessels from the periosteum penetrate the trabecula allowing the osteocyte to receive nourishment from the blood passing through the bone marrow. Spongy bone provides strength to stress areas in the bone and make the bone lighter.

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

Calcium is needed in the bones to make calcium carbonate and calcium phosphate which form the hydroxyapatite crystals that give the bone its hardness.

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) When calcium...