5.2.3 Quiz
List the 4 steps in healing a bone fracture in order.
1) Hematoma Formation 2) Fibrocartilage Callus Formation 3) Bony Callus Formation 4) Bone Remodeling
Osteoblast
A bone-forming cell
Parathyroid gland
A gland that regulates calcium, located behind the thyroid gland in the neck. The parathyroid gland secretes a hormone called parathormone (or parathyrin) that is critical to calcium and phosphorus metabolism.
Parathyroid horomone
A hormone of the parathyroid gland that regulates the metabolism of calcium and phosphorus in the body.
Calcitonin
A polypeptide hormone especially from the thyroid gland that tends to lower the level of calcium in the blood plasma.
Hematoma Formation
Blood vessels that are ruptured during the break swell to form a mass called a hematoma. This mass forms between the broken bones.
What influences bone development?
Bone development is influenced by what we eat, how we exercise, how our hormones function and even how much sun exposure we get.
Explain how the body will use bone remodeling to repair a fracture.
Bone remodeling is the replacement of old bone tissue by new bone tissue. It involves the processes of bone deposition or bone production done by osteoblasts and bone resorption done by osteoclasts, which break down old bone.
Why did a decrease in bone mass lead to increased calcium levels in the blood?
Bones are made from collagen and non-collagen proteins, and they are fortified with calcium. If a person does not take in enough calcium from their diet, the body extracts calcium from the bones, resulting in loss of bone strength and mass.
Explain why bone mass is "lost in space." Make sure to mention specific bone cells in your response. Do you think there is any way to fight this loss?
In a microgravity environment, because of reduced loading stimuli, there is increased bone resorption and no change in or possibly decreased bone formation, leading to bone mass loss at a rate of about ten times that of osteoporosis. Astronauts can reduce the risk of bone loss and renal stones by proper intake of appropriate nutrients, such as calcium and vitamin D, an effective exercise program and minimal amounts of medication.
What lifestyle choices help a person maintain healthy, strong bones and prevent bone loss? Explain.
Like a diet rich in calcium and vitamin D, exercise helps strengthen bones at any age. But proper exercise and diet may not be enough to stop bone loss caused by medical conditions, menopause, or lifestyle choices such as tobacco use and excessive alcohol consumption.
Fibrocartilage Callus Formation
New capillaries begin to form into the clotted blood in the damaged area. Connective tissues cells form a mass of repair tissue called a fibrocartilage callus. This callus contains some cartilage, some bone and collagen fibers and the combined mass closes the gap between the broken bones.
Bony Callus Formation
The fibrocartilage callus is gradually replaced by one made of spongy bone. This new mass is referred to as the bony callus. Osteoclasts and osteoblasts move to the area and multiply.
Why do you think a runner will most likely develop bigger leg bones than a swimmer? How does this happen?
They have more force they are using on their legs. It happens because the skeleton can adapt to certain situations.
Bone Remodeling
This process occurs in response to either the body's need for calcium or the pull of gravity on muscles and bone.
What is osteoporosis? How can a study of what is happening to bones in space potentially help prevent and treat this condition?
a bone disease that occurs when the body loses too much bone, makes too little bone, or both.In this mutual free-fall, bones no longer have to fight against Earth's gravity during locomotion. As a result, researchers suspect the root cause of bone loss in space is weightlessness.
Thyroid gland
a large ductless gland in the neck that secretes hormones regulating growth and development through the rate of metabolism
Osteoclasts
a large multinucleate bone cell that absorbs bone tissue during growth and healing.
