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.
The control in an experiment is a variable held constant due to its possible ability to be a nuisance in the experiment. In other words, it is a possible independent variable that the scientist has no interest in investigating.