Answer the following question given this paragraph: 

Figure 7.22 Osteoporosis Osteoporosis is an age-related disorder that causes the gradual loss of bone density and strength. When the thoracic vertebrae are affected, there can be a gradual collapse of the vertebrae. This results in kyphosis, an excessive curvature of the thoracic region.


Q: What is the age-related disorder that causes the gradual loss of bone density and strength?


A:
osteoporosis