Question

What are tropic movements? Given one example of each.

Answer 1

Hint: living organisms react differently to the stimulus and it presents in the environment. With the help of the plant's lack of nervous system, since the organs and the muscles, or they respond to the environmental stimuli-touch, light, gravity, etc. it brings said that, let’s find out the tropic movement in the plants and different types of it in detail.

Complete answer:
> Tropic movements -
The tropic movement or tropism as a directional movement of the particular parts of a plant in the response to the environmental stimuli. Now the movements are slow and either towards the stimuli and away from it. In general, a stimulus can be either positive or negative. To elaborate, a stimulus would be positive whether a plant moves towards it. On the other side, whether the plant moves away from it, the stimulus would be considered negative.

Types of movements in plants -
In total six types of tropic movements in the plant, they all are in the following-

> Phototropism: The directional movements happen due to phototropism and it occurs in light. The roots of this movement tend to move away from the light and the source indicates the negative phototropism. Example:- sunflower.

> Chemotropism: This type of tropism occurs in the reaction to chemical stimuli. It is the most common occurrence in the flowering plants. Example:- Tentacles movement in Drosera.

> Geotropism: In this type of tropism its response to gravity. In this process, the roots grow downwards to indicate a positive geotropism. Example:-closing of a flower.

> Hydrotropism: In this type of movement, it reacts to the presence of water. The motion of the result is known as hydrotropism. Example:-radish roots.

> Thigmotropism: Typically, this type of movement is reacted in the growth or any kind of movement is in response to a contact established with a solid object or surface. Example:- money plants.

> Thermotropism: It responds towards a change in an atmospheric temperature which is known as thermotropism. Example:-one type of curling leaves in Rhododendron.

Note: Tropic movement is a movement of the plant, This movement is in response to root and shoot growth.
The reason for the importance of tropic movements is due to:
- They give protection and help in developing a sudden response for change.
- They help in the development and growth of the plants.