Notes on Bone Growth and Development

Remodeling

The process by which bone is replaced and adapted to stress.

Calcium storage in bones

Bones store 99% of the body's calcium supply, essential for function.

Parathyroid hormone (PTH)

Hormone that increases calcium levels in the blood.

Calcitonin

Hormone that decreases calcium levels in the blood.

Fracture hematoma

A large blood clot that forms at the site of a fracture.

External callus

Cartilage and bone formed around the fracture during healing.

Internal callus

Cartilage and bone formed within the fracture site during healing.

Role of exercise in bone health

Exercise helps maintain bone strength and density.

Calcium ion regulation

Calcium levels in the body are tightly regulated for physiological functions.

Impact of inactivity on bone mass

Periods of inactivity can lead to a significant loss of bone mass.

What is the balancing act in bone growth?

Bone growth relies on a balance between osteoblast (formation) and osteoclast (resorption) activity.

What occurs to stressed bones?

Stressed bones become thicker and stronger.

What occurs to unstressed bones?

Unstressed bones thin and become brittle.

What is the initial step in the fracture healing process?

Formation of a fracture hematoma.

How does bone remodeling affect skeletal health?

It ensures the skeleton adapts to stresses and maintains bone strength.

What happens if calcium levels increase by 30%?

Neurons and muscles become unresponsive.

What is the consequence of a 50% decrease in calcium levels?

It can lead to death.