Each type of channel and each type of transport protein has a specific molecule that they transport. why would this be important to a cell?

The channels would only let in certain molecules in that would help the cell. The channels would not let some harmful bacteria into the cell this way with channels that only transport one molecule. 

Competition. interaction among organisms that compete for the same natural resource (food, shelter, water, space) in an ecosystem. predation. an interaction in which one organism kills another for food. predator. prey. symbiosis. mutualisum. commensalisum. parasitisum.

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