Question

Explain phototropism and geotropism in plants. Are there any similar examples in the animal world also?

Answer 1

If a plant is potted near a window, its stem will bend toward the light as it grows. The growth of a plant towards light is known as phototropism. In the same way, the roots of plants grow towards the earth and the stem grows in the opposite direction. This is an example of geotropism.

In animals, cockroaches and earthworms show negative phototropism. They move away from light. In the same way, Paramecium swims in the opposite direction of the Earth's gravity and shows negative geotropism.