Bananas belong to berries and grow in clusters like grapes. A banana can be clustered into 16 clusters, and the clusters are long beside the roots. In the process of growth, every banana has to stretch upward and face the light, so the banana bends slowly. Because there is auxin in plants, the side with more sunshine has more auxin, and the side with less sunshine has less auxin, which leads to uneven distribution of auxin. This is also the phototaxis of plants.

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Bananas belong to berries and grow in clusters like grapes. A banana can be clustered into 16 clusters, and the clusters are long beside the roots. In the process of growth, every banana has to stretch upward and face the light, so the banana bends slowly. Because there is auxin in plants, the side with more sunshine has more auxin, and the side with less sunshine has less auxin, which leads to uneven distribution of auxin. This is also the phototaxis of plants.