Essential nutrients
a. are made by the body
b. can only be supplied adequately with dietary supplements
c. must be obtained through diet
d. consist of over 75 different types of nutrients

the flagellates share a facultative mutualist association with termites. mutualism is a biological interaction between individuals of different species, where both benefit from each other. this is called cooperation and it differs from other interactions such as cases of exploitation, such as parasitism, predation. in this interaction called association, both species cooperate and benefit.