Differentiate Between Tropic and Nastic Movement: A Detailed Analysis

Last Updated: January 30, 2025

Differentiate Between Tropic and Nastic Movement: A Detailed Analysis

Plants exhibit many different kinds of movements in response to environmental stimuli, which can be classified into two: tropic and nastic. It is an important difference that students at the secondary level, when studying biology should know. This article aims to differentiate between tropic and nastic movement while also focusing on some important concepts, which are the 5 differences between tropic and nastic movement, mention any two differences between tropic movement and nastic movement, etc., and insight beneficial for class 10 students. Those who want further academic help can take online tuition classes to master these biological concepts.

What Is Tropic Movement?

Tropic movement is the directional response of plants to an external stimulus. This movement occurs due to differential growth in the cells of a plant, in which one side grows faster than the other and the plant bends towards or away from the stimulus. The most important feature of tropic movement is that it is directional and occurs in response to stimuli such as light, gravity, water, and touch.

Types of Tropic Movements

  • Phototropism: growth in response to light, that is, positive phototropism of the shoot towards light and negative one of the root away from light.
  • Gravitropism, or Geotropism: growth in response to gravity and roots grow straight down (positive gravitropism) whereas shoots grow vertically upwards (negative gravitropism).
  • Thigmotropism: growing in response to touch, with examples like those of climbing plants, where tendril wraps the support.
  • Hydrotropism: It is the direction of growth to moisture, by roots towards the source of water.
  • Chemotropism: Growth in response to a chemical stimulus, such as pollen tubes growing towards the ovule during fertilization.

What is the Nastic Movement?

Nastic movement is non-tropic as its movement does not depend upon the direction of stimuli but instead because of turgor pressure alterations within the cells of a plant. They usually are quick in action and very transitory whereas tropic movements include growth in them.

Some Examples of Nastic Movements

  • Thigmonasty: It is also called seismonasty; reaction to contact or mechanical stimulation; mimosa pudica responds quickly to be closed as a "Touch-Me-Not plant".
  • Photonasty: Movement according to the intensity of light, such as opening and closing of flowers in response to daylight.
  • Nyctinasty: Movement due to circadian rhythm, like folding of leaves at night.
  • Thermonasty: Response to change in temperature, such as tulip flowers opening in warm conditions and closing in cold conditions.

 From the above comparison, we can conclude 5 differences between tropic and nastic movements. Now, let’s have a look at the two major differences between the movements.

Mention Any Two Differences Between the Tropic Movement and the Nastic Movement

  • Tropic movement is directional and dependent upon the direction of the stimulus. Whereas nastic movement is non-directional.
  • Permanent growth changes occur in tropic movement, but nastic movement is mostly temporary and results from a change in turgor pressure.

How Online Tuition Classes Can Help in Understanding These Concepts

For students who are unable to differentiate between tropic movement and nastic movement class 10 syllabus topics, online tuition classes are the best option through which these biological concepts can be learned efficiently. Here, such classes present interactive lessons, experienced instructors, and practice exercises for the reinforcement of the learning process. Besides, students can clarify their doubts and excel in exams with the help of platforms offering online tuition classes.

The basic differences between tropic and nastic movements help a person appreciate how plants try to cope with their environment. Be it the directional growth responses of tropic movements or the rapid reversible movements of nastic responses, both help in the survival of the plants. For more detailed knowledge, students may take online tuition or search for relevant study material through online educational sources to enhance their knowledge and emerge as toppers in their classes.

Role of Hormones in Tropic and Nastic Movements

Plant hormones are used in both tropic and nastic movements of plants. One such plant hormone is auxins, which make the cells of the plant long and are mainly used in tropic movements like phototropism and gravitropism. This leads to differential growth with varying responses in plants that bend toward or away from the stimulus. However, nastic movements are generally regulated by changes in turgor pressure, and those are controlled by such plant hormones as abscisic acid and gibberellins. Such hormones help plants adjust quickly to environmental changes so they can conserve energy or protect themselves from likely harm.

Conclusion

Understanding tropic and nastic movements transcends the limits of books because it has real applications in agriculture and horticulture. Once this is understood tropic movements, farmers and botanists will be able to get absolute control over the amount of light exposure and moisture in the soil for their respective plants. Likewise, such knowledge will help protect crops of plants once such plants are discovered, like the Mimosa pudica, sensitive plants to changes in the environment. Understanding how plants respond to stimuli will allow scientists to create better farming techniques and improve the yield of the plant, thereby allowing for an automated system of precision agriculture. For students struggling with such comparisons, online tuition classes can make a huge difference. They can highly rely on the professionals.

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