Unregulated cell division can result in cancer
Answer:
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea.
Sea stars (or starfish) feed off the oyster beds. If the oyster beds were destroyed it would deplete the major food source of the sea stars and they would begin to diminish.
Predator and Prey relationships would have the most effect on an ecosystem's stability because they keep a limit number on the opposing population (ex. rabbit population can only get so high because wolves keep eating them / wolf population can only be so high because there is't enough rabbit to eat)