Which effect can be attributed to increased pressure on a bone?
A) Increased osteoblast activity
B) Increased osteoclast activity
The correct answer and explanation is:
The correct answer is A) Increased osteoblast activity.
When pressure is applied to a bone, a process known as mechanotransduction occurs, where mechanical forces are converted into biochemical signals that influence cellular activities. In response to increased pressure or mechanical load, the bone adapts by enhancing the activity of osteoblasts, which are the cells responsible for bone formation.
This response is part of the bone’s adaptive remodeling process. Osteoblasts produce bone matrix and contribute to the mineralization of the bone, making it stronger. The application of pressure or mechanical load causes small electrical charges on the bone’s surface, which stimulates osteoblasts to promote bone formation. This helps the bone to become more robust and capable of handling the increased stress. For instance, weight-bearing exercises, like running or lifting weights, can lead to stronger bones due to this mechanism.
In contrast, osteoclasts are the cells responsible for bone resorption, or the breaking down of bone tissue. These cells are activated when bones experience lack of mechanical stress or when there is a need to remove damaged or excess bone material. However, in response to pressure or mechanical load, osteoclast activity is generally not increased.
The balance between osteoblast and osteoclast activity ensures that bones remain both strong and flexible, adapting to the mechanical demands placed on them. Increased osteoblast activity in response to mechanical stress ensures that bones maintain their structural integrity, becoming more capable of handling future loads. This dynamic process plays a crucial role in maintaining bone health and strength, particularly during physical activities and as we age.