Question

A plant appears to grow away from the sunlight and the roots appear to grow deeply straight down into the ground. This plant is displaying which of the following?

Answer 1

The answer is negatively phototropic and positively gravitropic.

Phototropism is reaction of a plant to a light stimulus. Growth of the plant or its part grow towards the light stimulus is called positive phototropism. Growth of the plant or its part away from the light stimulus is called negative phototropism. Since, the plant grows away from the sunlight (away from the light stimulus), it is negatively phototropic.

Gravitropism is reaction of a plant to gravity. Growth of the plant or its part in the same direction as gravity is called positive gravitropism. Growth of the plant or its part grow in the opposite direction of gravity is called negative gravitropism. The root is positively gravitropic (grows deeply straight down into the ground, in the same direction as gravity).