The trophozoite stage of Entamoeba histolytica is the active, feeding stage of the parasite. It is characterized by a single nucleus and large cytoplasm that contains several vesicle and granules. The trophozoite is usually pear shaped and measures approximately 10-60 micrometres in length. After the trophozoite are released then they travel through the intestine, where they feed on bacteria and other microorganisms. They can also invade the intestinal wall and cause tissue damage, leading to symptoms such as diarrhoea, abdominal pain, and bloody stools. Some trophozoite may also enter the bloodstream and migrate to other organs such as the liver here they can cause abscesses. This is known as extraintestinal amoebiasis. After several days, the trophozoite begin to encyst in the large intestine. Encystation is the process by which the trophozoites transform into dominant cyst stage, which is resistant to environmental stresses such as desiccation and temperature change. 1. mention 10 keypoints of this entamoeba hystolytica lifecycle 2. give the book reference of this information.