Table of Contents
Types of Movement in Plants
There are five types of movement in plants:
1. Growth – This is the process of increasing in size, both in height and width. It is primarily due to cell division and expansion of the cells.
2. Reproduction – This is the process of creating new plants from existing plants. It includes both sexual and asexual reproduction.
3. Movement – This is the ability of plants to move their parts in response to stimuli. This includes movement of the leaves, flowers, and stems.
4. Absorption – This is the process of taking in nutrients and water from the soil.
5. Transpiration – This is the process of losing water from the leaves. It is necessary for cooling the plant and for the transport of water and nutrients from the roots to the leaves.
Tropic Movement:
A tropic movement is a type of movement that occurs when an object is displaced from its original position and moves towards the equator. This type of movement is often caused by the Earth’s rotation, which creates a centrifugal force that pulls objects towards the equator. The tropic movement can also be affected by the Earth’s gravitational pull, which pulls objects towards the center of the Earth.
Types of Tropic Movements:
There are three types of tropic movement:
-tropic of cancer
-tropic of capricorn
-tropic of cancer
The tropic of cancer is the imaginary line that marks the northernmost latitude at which the sun can be directly overhead. The tropic of capricorn is the imaginary line that marks the southernmost latitude at which the sun can be directly overhead. The tropic of cancer is located at 23.5 degrees north latitude, and the tropic of capricorn is located at 23.5 degrees south latitude.
Phototropism:
The directional growth of a plant in response to light is called phototropism. The stimulus for phototropism is light, which is detected by the plant’s photoreceptors. There are two types of photoreceptors in plants: blue light receptors and red light receptors.
Blue light receptors are sensitive to the short-wavelength light in the blue part of the spectrum. Red light receptors are sensitive to the long-wavelength light in the red part of the spectrum.
When a plant is exposed to light, the blue light receptors are activated and the red light receptors are inhibited. This causes the plant to grow in the direction that is away from the light source.
Geotropism:
Geotropism is the directional growth response of a plant or plant part to gravity. The term was first proposed in 1875 by the German botanist Karl Goebel. The term geotropism is derived from the Greek words γῆ (gē, “earth”) and τροπή (tropē, “turning”).
Chemotropism:
A plant’s growth is directed by various stimuli, including light, gravity, and chemicals in the soil. One type of stimulus, called a chemotropic stimulus, is a chemical that causes a plant to grow in a particular direction. For example, auxin, a plant hormone, is a chemotropic stimulus that causes plants to grow towards the light.
Hydrotropism:
Movement of a plant organ in response to a stimulus from water.
The stimulus for hydrotropism is the presence of water in the environment. The plant organ moves towards the water to increase its exposure to the water and to increase the uptake of water. This movement is usually towards the soil, but can also be towards other surfaces that are wetter than the surrounding environment, such as a water droplet or another plant.
Thigmotropism
A plant’s response to touch, thigmotropism is a directional growth response to physical contact. The plant grows towards or away from the source of the contact. This response is usually due to a change in the turgor pressure of the plant’s cells.
Nastic Movement:
Nastic movement is a kind of movement that is not under the control of the brain. This means that the organism can move in a certain way without having to think about it. For example, a plant that is wilting can still move its leaves to get sunlight. This is an example of nastic movement.
Key points:
Plants move in response to environmental stimuli, such as light, gravity, water, touch, and chemical gradients.
Plants can move in response to light by phototropism, where the plant bends towards the light. This is due to the auxin hormone which is produced in the leaves and moves towards the shoot tip.
Plants can move in response to gravity by gravitropism, where the plant bends towards the ground. This is due to the starch grains which are located in the root and move towards the shoot.
Plants can move in response to water by hydrotropism, where the plant bends towards the water. This is due to the water molecules which are attracted to the plant.
Plants can move in response to touch by thigmotropism, where the plant bends towards the touch. This is due to the plant cells which are sensitive to touch.
