How does adding or removing organisms and introducing diseases to a population affect the energy flow
within our ecosystem?

Adding or removing organisms and introducing diseases to a population affect the energy flow within our ecosystem:When there is the addition of any organism at any level then there will be scarcity of food (preceding tropic level) that they feed on also when organism is removed then organism of succeeding tropic level.Number of individual living at a particular region at a particular time is called population. Different population makes community and interaction of a different community and the non-living things forms ecosystem. There are different tropic levels in ecosystem producer, 'primary consumer', 'secondary consumer' and 'tertiary consumer'. Amount of the 'flow of energy decreases' from producer to tertiary consumer.

Decreased genetic variation is the answer. 

A. it splits a cell into two new daughter cells.