The digestive system is made up of the gastrointestinal tract—also called the GI tract or digestive tract—and the liver, pancreas, and gallbladder. The GI tract is a series of hollow organs joined in a long, twisting tube from the mouth to the anus. The hollow organs that make up the GI tract are the mouth, esophagus, stomach, small intestine, large intestine, and anus. The liver, pancreas, and gallbladder are the solid organs of the digestive system.
While most of us know that we need to schedule routine maintenance for our cars and even our heating and A/C systems before they break down rather than waiting for disaster to strike, sometimes we're not quite as conscientious when it comes to our own health and well-being. Sure, we might undergo an annual physical each year, but unless we're complaining of any particular symptoms, such a checkup might not amount to much more than a weigh-in, a stethoscope to the chest, and maybe a hammer to the knee to check if you're still alive and (literally) kicking.
There is no denying that many people love white teeth, on themselves as well as on others. Having white teeth is not only aesthetically appealing to most people but it also has a psychological reason behind it. According to Dr. Dacher Keltner, a professor of psychology at the University of California, Berkeley, most people are attracted to white teeth because they appear to be cleaner and healthier as compared to stained or yellow ones