Answer:
B.
The flagellates and termites share an obligate mutualistic association
Explanation:
Organisms of same or different species tend to interact with one another in an ecosystem. The close interaction between two organisms is referred to as SYMBIOSIS. A type of symbiotic relationship is MUTUALISM, which is when both organisms benefits from the relationship.
However, mutualistic relationship can be of different types depending on how dependent the involved organisms are on each other. The example in this question illustrates OBLIGATE MUTUALISM, which is when the organisms involved in the mutualistic relationship depend on one another for survival. This is the case of the termites and the flaggelates where the termite depends on the flaggelate for enzymes that helps them digest cellulose while the flaggelates depend on termite for nourishment/food.
The termite will not survive if it doesn't get enzymes to digest its cellulose while the flaggelates will also not survive if they do not get nourished. Hence, the two organisms share an OBLIGATE MUTUALISTIC RELATIONSHIP.
Answer:
Four abiotic forms of nitrogen cycle and its chemical formula
Ammonium – 
Ammonia – 
Nitrite – 
Nitrate – 
Explanation:
Ammonium: In the nitrogen cycle ammonium is starting point that is present in soil and are converted to various forms by different process.
Ammonia: In the process of nitrogen fixation, the bacteria having nitrogenase enzymes reacts with the nitrogen as well as hydrogen and produces the ammonia, which is further converted to organic compounds.
Nitrite: The nitrosomonas bacteria present helps in conversion of nitrogen gas into nitrite.
Nitrate: Again the Nitrite is converted into Nitrate by the nitrobacter. During the process of assimilation ammonium and nitrate are absorbed by the plants.
