Question

Which one is non-pathogenic? A. Entamoeba coli B. Entamoeba histolytica C. Entamoeba gingivalis D. Plasmodium ovale

Answer 1

Hint: A pathogen is an external agent that causes diseases in healthy organisms. First they cause infection and after that they develop if the system in the body is weak. Some of the infective agents may be biohazard as it causes disease to the host.

Complete answer:
Once the pathogen is within the host body it manages to avoid the body’s immune responses and uses the body resources to duplicate in the target region of the host. Pathogens use different routes to infect organisms like from the skin, air borne particles, contact with feces etc. Virus, bacteria, fungi and parasites are the different types of pathogens which cause different diseases in organisms. Entamoeba coli is a non- pathogenic species of Entamoeba found in the human gastrointestinal tract. The morphology of Entamoeba coli is of Trophozoite and cyst stage. The trophozoite stage contains only 1 nucleus with no chromatid whereas in the cyst stage there are nuclei and chromatids. Humans develop Entamoeba coli by ingesting cyst in fecally contaminated food like drinks etc. Entamoeba histolytica is one of the infectious parasites which is found in the human intestine. It is a protozoa parasite which causes disease amoebiasis in the gastrointestinal tract. Amoebiasis is the parasitic infectious disease which is transmitted through the contaminated foods. This parasite is unicellular which can infect both humans and animals. Entamoeba gingivalis is a part of our normal oral microbiota. People suffering from poor oral hygiene have these microorganisms. They are generally surrounded on teeth and gums. They feed on the nutrients present within the epithelial tissue of the mouth. It is transmitted from kissing, toothpicks etc. Plasmodium ovale is an uncommon parasite which causes tertian malaria but not fatal. Malaria is the disease caused by the bite of an infected anopheles mosquito.

Hence, the correct answer is option (A).

Note: The role of pathogens is to exist and multiply in its host. The pathogens target a compatible body type which contains a lot of nutrients, infect the host, avoid the host's natural immune system, reproduce and enter a new host.