Think about the environment where your phytoplankton will live and the needs it will have. What shape will your phytoplankton (model) have? How large will your phytoplankton be? Your model will be much larger than an actual phytoplankton, but you need to consider what effect size will have on your model's sinking rate. How heavy will it be? What structures will it have to affect its sinking rate? What color will it be?

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