The first one with the boxing crab and anemone is mutualism.
The second one with the dog and flea is parasitism.
Scientists most often produce new genetic variations of organisms by causing mutations with radiation or chemicals and then selectively breeding in order to emphasize the desired traits in the new variations. The Dachshund is an example of this. By breeding two dogs with a similar mutation that caused student legs and elongated backs breeders were able to create a new variation not found in nature.
An enzyme lowers the activation energy of a reaction so it can take place within living organism, so an enzyme is a biological catalyst.