Note to imply that our immune system has also worked as a mucosal epithelium is to detect microorganisms with enamel coating. With regard to the work of the small hairs (cilia) which can be found in the respiratory tract, such as nasal help sweep foreign substances or microorganisms to move to the bronchial or nasal cavity. And excreted from the body by coughing, sneezing or excreted in the sputum. That could spit out or swallow the stomach is then excreted in the feces. In addition to the nasal cavity Mechanisms to prevent foreign matter such as this. May be found by opening the body parts as well.