In this article we will discuss about the structure of giardia lamblia. This will also help you to draw the structure and diagram of giardia lamblia.
Giardia lamblia (also known as G. intestinalis) lives as a flagellate parasite in the small intestine of man. It causes a disease called giardiasis which causes digestive disturbances. Heavy infection interfere with normal absorption as the flagellates adhere to the mucosa.
Giardia presents both trophic and cystic forms. Trophozoite. The trophozoites measure 9-20 micra by 6-20 micra. The protoplasm of the oval body is clear. The body is flattened dorso- ventrally. The dorsal surface is convex.
A bean-shaped sucking disc is present on the ventral surface of the broad or anterior end. Two flagella emerge from the posterior end while three other pairs of flagella extend from the lateral and anterolateral surfaces. There are two nuclei with prominent nucleoli. The axostyles are paired.
Two parabasal bodies, sometimes fused, lie close to the axostyle and in the posterior third of the body. Cyst. The cysts measure 8-14 micron by 6-10 micron. The cysts contain 4-16 nuclei, axostyles, parabasal bodies and fibril (Fig. 50F).
The trophozoites transform to cysts and reproduction within the cyst occurs by binary fission.
Cysts come out with stool. Infection occurs through contaminated food or drink.