In interviews within our studies, students revealed their conceptions of cell division and climate change. Their conceptions of these topics are far from the current scientific theory, but they still make sense to the students. Employing the theory of experientialism, we argue that students use imaginative thinking, that is, metaphors to understand the imperceptible world of cell division and climate change. This metaphorical understanding is achieved by conveying the structure of a source domain to a target domain. Usually the source domain is a conceptual structure grounded in bodily experience that is understood directly. The source-to-target mapping that leads to this kind of understanding is done unconsciously. It functions like a hidden hand that shapes everyday conceptual understanding of abstract target domains in the microcosm and macrocosm. We identify and characterize common source domains that lie in the perceptible mesocosm to understand biological phenomena in the microcosm (cell division) and macrocosm (climate change). Furthermore, we present successful representations that foster students understanding of these phenomena.