Christiana Strysko

Critical Thinking Assignment #2: Osteoporosis: Marissa, Jeremy, and Eleanor By: Lisa Rubin

Scenario A:
1. Bone physiology is responsible for homeostasis and the metabolism of the bone structures. Homeostasis of the bones requires osteoclasts and osteoblasts for bone remodeling, which is the process of removing mature bone tissue and forming new bone tissue. Osteoclasts are cells that are responsible for the breaking down of bone tissue, and osteoblasts are cells that are responsible for the building up of new bone tissue. This process of bone remodeling is extremely important for healing and healthy, strong bones. Two of the most prominent types of bone tissue are the compact bone and the spongy bone. The compact bone is the outer portion of the bone that is very hard and dense, and is homogenous. The spongy bone is the inner portion of the bone, which is a heterogeneous mixture, composted of flat pieces of bone and fatty marrow. The compact bone protects spongy bone.

2. Calcium is an extremely important component that is essential for maintaining homeostasis in our bodies. Calcium is always being used throughout the body, and is often lost through bodily processes. Because bones contain much calcium, the body may source calcium away from the bones when an individual’s diet does not contain enough calcium. This process weakens the bones.

3. The body controls calcium levels in the bones and blood through the parathyroid hormone and through calcitonin. The parathyroid hormone is a secretion of the parathyroid gland that increases the concentration of calcium in the blood by collecting calcium from the parathyroid hormone receptors and distributing it into the blood stream. Calcitonin has the opposite effect of the parathyroid hormone, reducing the amount of calcium in the bloodstream by stimulating osteoblastic activity in bones.

4. Because osteoporosis mainly affects the osteoblastic activity in the bones, it causes the bones to become more fragile than usual. The bone matrix maintains homeostasis by a healthy amount of activity between the osteoclasts and osteoblasts. Because the osteoclasts are the only cells working on the bones when they are infected with osteoporosis, then the bones are constantly being broken down, and never being replaced and built up. This causes the bone matrix to suffer fractures and decrease in bone mass, which is not remodeled due to the lack of activity from the osteoblasts.

5. Although osteoporosis has many non-genetic factors contributing to the risk, it has been determined that osteoporosis may have significant genetic risk factors. Because at this point in time it has been too difficult to gage the amount of risk facing those with a history of osteoporosis, scientists have not yet established solid evidence leading to the conclusion that genetics are a primary factor. Currently new information is being discovered on a nearly daily basis regarding the discovery of genetics playing a role in osteoporosis.

6. The controllable risks of osteoporosis include low calcium intake, excessive alcohol use, smoking, inadequate exercise, and prolonged use of medicines like steroids, antacids, and anticonvulsants. The uncontrollable risks of osteoporosis include gender, age, early menopause in women, amenorrhea (absence of menstruation due to normal or abnormal conditions), low testosterone levels in men, race and ethnicity, small or thin body frame, endocrine disorders, and chronic disease of the lungs, kidneys, stomach, and intestines.

7. Tell-tale symptoms of osteoporosis include backaches, a gradual loss of height, stooping in posture, easily occurring bone fractures, and fractured or collapsed vertebra.

Scenario B.
1. Calcium is essential for bone health because it optimizes bone mass, making them strong and less susceptible to osteoporosis. If an individual does not get enough calcium in their diet then the body will source calcium from the bones, so