Parasitic sort is a term used to describe organisms that rely on other organisms for their survival. The two most common examples of this type of organism are sponges and leeches. Sponges are aquatic animals that filter water for food and oxygen, while leeches are blood-sucking parasites that feed off of the blood of other animals. Both of these organisms are dependent on other organisms for their survival, making them a part of the parasitic sort.