Describe how different environmental factors affect the direction of growth of roots and the direction of growth of shoots.

environmental factors such as gravity and light enable plants to grow in the correct direction, in the case of shoots, they exhibit positive phototropism, growing towards a light source, and in the case of roots, positive geotropism is exhibited, causing them to grow towards the direction of gravity. shoots will also use negative geotropism in order to grow upwards when underground in the soil. the direction is controlled by a hormone called auxin which causes an uneveness of growth in the shoot or root, so one side is longer, causing it to bend in the intended direction