Posted: February 2nd, 2017

Explain the relationship between calcium and bones.

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 connective tissue made up of a variety of bone cells and extracellular matrix space. Bone tissue is mostly made up of osteocytes, osteoclasts and osteoblasts. Osteocytes maintain bone tissue through enzyme secretion. Osteoclasts use enzymes to break down bone matrix releasing calcium. Osteoblasts produce and secrete ground substance and collagen fibers to stimulate bone growth. The bone’s extracellular matrix space is continuously remodeling as stresses are put on it. The collagen provides structural support, tensile support and bone flexibility.
2. Explain the relationship between calcium and bones. (1 point)

Calcium is a much needed nutrient for bone’s strength and density. Bones store calcium in it so that bone mass is maintained.

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)

The body stores calcium so that it can be used when bones face fractures or any other stress. The Parathyroid hormone is responsible for blood calcium level. It is released whenever the blood calcium levels are low by stimulating the osteoclasts to release calcium into the bloodstream. Calcitonin is a hormone that acts against the parathyroid hormone by inhibiting the o