I know exactly where to go!

The roots of plants usually grow downwards. In contrast, all stems and stems grow upwards. But how does this work?
When plant seeds are in the soil, it is dark. So how can the plants distinguish between up and down?
Plants have a sense of gravity, which helps them to find the right orientation. As a result, the roots grow downwards and the shoot finds its way to the surface. This mechanism is called gravitropism.


    Experimental setting

    • Plant a seed or seedling of any desired plant in a small pot or glass
    • At the time when the seedling is about 3 cm high, put the pot/glass on the side
    • Be careful that it can not roll away of fall down!




    • Directly after putting the pot/glass on the side, the seedling is directed downwards. But already after 3 days you can see that it starts to grow upwards again because it can "sense" where up and down really is.

    You need

    • A pot or glass
    • Soil
    • A seed or shoot of any desired plant (e.g., sunflower)
    Heinrich Heine University
    University of Cologne
    Max Planck Institute for Plant Breeding Research
    Forschungszentrum Jülich