Question

How are protozoa harmful

Answer 1

Protozoan are harmful to humans because they cause various diseases. For example, the protozoan, Entamoeba histolytica causes amoebiasis which is amoebic dysentery and Giardia causes giardiasis which is dysentery. Plasmodium causes malaria. Trypanosome, a parasitic protozoan which lives in the bloodstream of human beings, cattle and other animals, causes a dangerous disease called sleeping sickness.