Entamoeba Histolytica

INTRUDER

INTRODUCTION

* Entamoeba histolytica is unicellular and is oval shaped.

* It is a eukaryotic micro-organism. (The nuclear genetic material is enclosed within a specialized membrane).

* It is a protozoan parasite.

* Amoebiasis is a disease caused by Entamoeba histolytica.

* It is also called as amoebic dysentery.

Entamoeba histolytica

TAXONOMY

* Common name : Ameba

* Kingdom: Protista

* Phylum: Protozoa

* Class: Lobosea

* Order: Amoebida

* Family: Entamoebidae

* Genus: Entamoeba

* Species: histolytica

MORPHOLOGY

* They are microscopic in nature.

* They move with means of pseudopodia.

* They reproduce by binary fission.

* They belong to the Class 1 Rhizopoda of Phylum Protozoa.

* There are two forms of Entamoeba histolytica -

1. Cysts

2. Trophozoites

CYSTS

* Cysts are infective.

* They only exist outside the host.

* They are round and is usually 10-15 micrometres in diameter.

* They are non-motile.

* They are surrounded by a wall that includes chitin to help survive the acid in the stomach.

The mature cyst has four smaller nuclei.

TROPHOZOITES

* Trophozoites is non-infective.

* They exist inside the host and in fresh feces.

* They are highly motile.

* They reproduce by binary fission.

* The nucleus is uniform and closely packed fine granules of chromatin.

* Trophozoites ingest red blood cells and absorbs their nutrients to survive.

* Some trophozoites transform into cysts.

MOTILITY

* They are highly motile.

* This is an essential feature of the pathogenesis and morbidity of amoebiasis.

* They move by means of pseudopodia.

REPRODUCTION

* When people feed on contaminated food or water, the cysts are transported to the small and large intestines....