Question

Cell elongation in plants is caused by………..
A)Auxin
B)Gibberellin
C)Florigen
D)Traumatic

Answer 1

Hint: It is a plant hormone that is produced in the tip of the stem and promotes the elongation of the cell. This is usually found at the dark side of the plant and causes cells to grow in comparison to the lighter side of the plant.

Complete answer:
-The elongation of the stem is promoted by an Auxin. It maintains apical dominance and enables the growth of the lateral buds.
-Oxygen is mainly produced in the tips of stem buds and roots. An example is IAA (Indole Acetic Acid).
-It is a type of plant hormone which produces in the tip of the stem and promotes cell elongation.
-Auxin migrates to the darker side of the plant and there they enhance the growth of the cell in comparison to the lighter side of the plant. It makes the stem tip bend towards the light and this type of moment of the stem is known as phototropism.
-Auxin also plays a major role in the maintenance of apical dominance. Most of the plants have little birds that are present at the nodes of the stem.
-Buds are embryonic meristem and they maintain their dormant state. Auxin helps in maintaining this dormancy. Therefore as long as the required quantity of auxin is produced by lateral meristem the lateral buds will remain in their dormant state

Additional Information: -gibberellin also promotes this time along with action but they are not produced in the tip of the stem. It is the first class of hormones to be discovered.
-Florigen controls or triggers the flowering in the plants.
-Traumatic acid is a wound-healing agent in the plants. It stimulates the cell division near the trauma site and forms a protective callus which heals the damaged tissue.

So, the correct answer is,” Auxin”

Note: -Whenever there is permanent enlargement of the cells formed by the differentiation then this is known as the elongation.
-The permanent increase in the surface of the cell wall is known as cell elongation.
-A hormone produced in the tip of the stem and promoting the elongation of the cell is known as Auxin.