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.
Everything else in a controlled experiment is held constant, to help reduce extraneous factors (confounding variables). In a simple controlled experiment, only one variable is manipulated (the independent) and one is tested (the dependent). However, with increasingly complicated experiments, you can manipulate multiple independent variables and measure multiple dependent variables.