1. Take two glass troughs A and B and fill each one of them two-thirds with soil. In trough A plant a tiny seedling. In trough B plant a similar seedling and place a clay pot inside the soil. Water the soil in trough A daily and uniformly. Do not water the soil in trough B but put some water in the claRead more

    Take two glass troughs A and B and fill each one of them two-thirds with soil. In trough A plant a tiny seedling. In trough B plant a similar seedling and place a clay pot inside the soil. Water the soil in trough A daily and uniformly. Do not water the soil in trough B but put some water in the clay pot. Leave both the troughs for a few days.
    Now, dig up the seedlings carefully from both the troughs without damaging their roots. We will find that the root of seedling in trough A is straight. On the other hand, the root of seedling in trough B is found to be bent to the right side i.e., towards the clay pot containing water.
    In trough A, the root of the seedling gets water from both sides. But in trough B, the roots get water oozing out from the clay pot which is kept on the right side. Therefore, the root of seedling in trough B grows and bends towards the source of water to the right side. This experiment shows that the root of a plant grows towards water. In other words, the root of a plant is hydrotropism.

    See less
    • 3
  2. When the tip of a tendril touches a support, then the auxins present in its tip move to that side of tip which is away from the support. Auxins promote growth. So, due to more auxins in it, the side of tendril away from the support grows faster (and becomes longer) than the side which is in contactRead more

    When the tip of a tendril touches a support, then the auxins present in its tip move to that side of tip which is away from the support. Auxins promote growth. So, due to more auxins in it, the side of tendril away from the support grows faster (and becomes longer) than the side which is in contact with the support and makes the tendril twirl (or bend) around the support.

    See less
    • 3
  3. Movement of leaves of the sensitive plant It is a nastic movement which does not depend on the direction of stimulus applied. The stimulus is touch. Movement of a shoot towards light It is a tropic movement which depends on the direction of stimulus applied. The stimulus is light.

    Movement of leaves of the sensitive plant
    It is a nastic movement which does not depend on the direction of stimulus applied. The stimulus is touch.

    Movement of a shoot towards light
    It is a tropic movement which depends on the direction of stimulus applied. The stimulus is light.

    See less
    • 3
  4. Plant hormones are the chemical substances which help in controlling growth, flowering, height, development of plants and their response to the environment. Different types of plant hormones are – auxins, gibberllins, cytokinins, abscisic acid and ethylene.

    Plant hormones are the chemical substances which help in controlling growth, flowering, height, development of plants and their response to the environment.

    Different types of plant hormones are – auxins, gibberllins, cytokinins, abscisic acid and ethylene.

    See less
    • 3