Did you know that your small intestine is nearly six meters long? Or that there are about 60 muscles in your face, and you use 40 of them to frown but only 20 to smile? How about the fact that our bodies consist of 73 percent water, and that our hearts beat over 100,000 times each day? 

        The human body is an amazing and also complex machine. From the day we are born, our bodies grow and change in response to our environment, diet, and habits. The body has many different organ systems and parts that work together to allow us to breathe, move, see, talk and digest food all at the same time. Most of the time we are unaware of what is happening in our bodies; usually it is only when we get sick or feel pain that we notice. 

         Like machines, different body parts sometimes wear down from old age. People over the age of 65 are more likely to fall and hurt themselves, and these injuries—from bad cuts to broken bones—usually require serious medical attention. Due to the increase in the population of elderly people, gerontology is now one of the fastest growing areas of medicine. There are many treatments available to help older people recover from illness and injury. It is now common for older people with damaged joints, for example, to have surgery to replace the old joint with a new one made of plastic or metal. Instead of suffering aches and pains through their retirement days, older people are able to lead happier and more comfortable lives.