Bone mineral density (BMD) is a measure of bone strength. Studies show that BMD declines after age 45. The impact of exercise may increase BMD. a. True
b. False

As you age, your body may reabsorb calcium and phosphate from your bones instead of keeping these minerals in your bones. This makes your bones weaker. When this process reaches a certain stage, it is called osteoporosis. Many times, a person will fracture a bone before they even know they have bone loss.

air, water, heat and noise pollution can all be caused by producing and using technology. consuming resources - non-renewable resources, including precious metals like gold, are used to make technology