Depends on the size and shape of the plastic piece.
It's the same for any species swallowing something that can't be digested.
It might pass right through w/o bothering the shark. It might do some damage that the shark recovers from. It might do some lasting damage making the shark permanently weakened. It might do enough damage, either through causing a blockage or through tearing to kill the shark either rapidly or slowly.
There would b 2 much plastic nah crap Sherlock maybe try a smarter answer "there would b 2 much plastic" omg
If people did not recycle, then the supply of plastic would run out much faster.
She is still very much alive in her Missionary Sisters who continue her work.
Things would break down extremely slowly (mostly from ultraviolet and abrasion), much like what happens today with most plastic.
Unless it's moved to extremely cold situations, not much. The squirrel is a very adaptable animal and lives pretty much everywhere already.
Depends on the animal. Some animals would be able to adjust fine, especially small animals. But some animals are too fragile or large to be able to handle that much extra weight.
blah blah blah
Well, as itt happens. I happen to be an Animal Biologist myself, not allowed to tell you how much I earn, its private *tapping nose* ;)
There would be floods
Well then you're in for a bit of trouble. Cattle should have access to water at all times. As for eating too much, this depends on what that animal has eaten that you consider it "eating too much." Chances are that you would have a much bigger problem if the animal doesn't have water than it would of eating too much, however gut impaction can happen if the feed is too high in fibre, and if there's not enough moisture in the feed to sustain the animal.
Too much air would harm the body
It would happen at a much, much slower rate.