The digestive system is considered a natural nonspecific defense system against microorganisms as a result of:
a. the esophagus produces acid that kills mi-croorganisms prior to establishing a ga-strointestinal infection.
b. the peristalsis of the intestines prevents attachment of organisms that are capable of surviving the acidic pH of the stomach.
c. most organisms are resistant to the diges-tion by normal gastrointestinal secretions.
d. the organisms are killed by exposure to saliva and pancreatic secretions before and after leaving the stomach.
B
The digestive system consists of several factors that assist in the nonspecific elimination of a va-riety of infectious agents. These include chewing, digestive enzymes included in the saliva and the stomach as well as the physical nature of peristalsis that prevents the organisms from attach-ing to the mucosal surface and preventing attachment and invasion.
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