is bladderwort a producer of a consumer. An animal that can't produce its own food and it eats plants and other animals. That is what a consumer is.
If it is; What is the purpose of a control in verifying a hypothesis or conducting an experiment, it is: Controls are needed to eliminate alternate explanations of experimental results. That is in order to test a particular variable you need a control. For e.g.
Microbiological control in the food industry plays a critical role in preventing Salmonella outbreaks. Tests and media used for identification of Salmonella take advantage of unique aspects of Salmonella physiology or biochemistry relative to other genera within the family Enterobacteriaceae.