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.
By definition the control in a science experiment is a sample that remains the same throughout the experiment. The control must remain the same or equal at all times in order to receive accurate results. You can have as many controls as necessary to achieve results.