Â© 2013 WebMD, LLC. All rights reserved. The teeth are the hardest substances in the human body. Besides being essential for chewing, the teeth play an important role in speech. Parts of the teeth include: â¢ Enamel: The hardest, white outer part of the tooth. Enamel is mostly made of calcium phosphate, a rock-hard mineral. â¢ Dentin: A layer underlying the enamel.
While they are often used synonymously, the terms infectious disease and communicable disease do not have the same meaning. A communicable disease is an infectious disease that is easily spread from one human to another.
A answered. An infectious disease is a disease caused by a microorganism and therefore potentially infinitely transferable to new individuals. It may or may not be communicable. An example of a non-communicable disease is disease caused by toxins from food poisoning or infection caused by toxins in the environment, such as tetanus. A communicable disease on the other hand is an infectious disease that is contagious and which can be transmitted from one source to another by infectious bacteria or viral organisms. The presence of the CDC logo and CDC content on this page should not be construed to imply endorsement by the US Government of any commercial products or services, or to replace the advice of a medical professional.