Plankton is not the name of a plant or animal but more of a category for any drifting organism that inhabits the middle to upper levels of the ocean, namely the pelagic zone.
Most vets do spays, neuters, bone surgeries, spleen surgery, tumor removals, and intestinal surgeries. Heart surgery and more complicated surgeries are done by specialists that requires more schooling. If you want to be a vet, you have to have REALLY good grades and Vet school is MUCH harder to get into than human medical school.
1 Nurse anesthetists Nurse anesthetists work in the surgical operating room, providing patient care during surgery. This includes administering powerful medication to prevent pain during surgery, administering medication to put a patient to sleep during surgery and monitoring vital signs during a surgical operation.