. Within ecosystems, the process of (1)_
takes
place. For this to happen successfully, there has to be
an originating (2)_ one example being a (3)_
Following the growth of this organism, another
will typically follow, like (4) _. For everything to
grow and develop successfully, organisms rely on one
another and develop relationships. Symbiotic
relationships of all types occur, for example (5)_

Consider a culture medium on which only gram-positive organisms such as staphylococcus aureus colonies can grow due to an elevated nacl level. a yellow halo surrounds the growth, indicating the bacterium fermented a sugar in the medium, decreasing the ph as a result and changing the color of a ph indicator chemical. this type of medium would be referred to as a differential and enrichment culture.