How is phagocytosis in the immune system different from protozoan phagocytosis? how is phagocytosis in the immune system different from protozoan phagocytosis? there is no difference between the two. protozoan phagocytosis is used to fight infection; phagocytosis by immune cells is used to feed the cells. protozoan phagocytosis is used for feeding; phagocytosis by immune cells is used to fight infection?

Phagocytosis is defined as a process of ingestion of bacteria or other infectious agent by phogocytes.

In human beings, the major and professional phagocytes are White Blood cells. These cells are specialized in attacking infectious agents that enters the body and kill them by engulfing them.  

In protozoan, the phagocytosis starts with the ingestion step, in which an infection agent is taken up by protozoans and form a special vacuole like structure which secretes lysosomes enzymes that attack the agent and kill it and then removed from body by egestion.  

Hence, there is not any significant difference between the process of phagocytosis in humans and protozoan; however the steps included vary in both.