SYMBIOSISSymbiosis: This comes from a Greek word simply meaning 'living together' and can be used to describe any association between two organisms.
Mutualism: This can be used to describe an association in which both organisms apparently benefit
Example: relationship between bullhorn acacia trees and certain species of ants.
Parasitism In this association one organism benefits, and the other is adversely affected. This description would also fit the relationship between a carnivore and its live prey and a herbivore and the plant it feeds on, especially if they are very specialized in the food they eat.
Example:Fleas and mosquitoes feed on blood from other organisms.
Commensalism is a type of relationship where one of the organisms benefits greatly from the symbiosis. The other is not helped but is not harmed or damaged from the relationship. In other words, this is a one-sided symbiotic relationship.
Example: the relationship between cattle egrets and cattle.