**Hormones** are substances produced by an organism that help in their development and homeostasis. Plant hormones specifically work in the growth and development of plant species, and helps in the regulation of plant’s response to the external environment and its varying conditions.

The four types of hormones are auxins, gibberellins, cytokinins, and ethylene.

Auxins affect the cell elongation in seedlings. They are responsible for phototropism and gravitropism.

Gibberellins increase the growth rate of stems and fruits.

Cytokinins trigger cell division, growth of lateral buds, and germination of dormant seeds.

Ethylene stimulates the ripening process in fruits.

Auxins trigger vertical growth, wherein the cell elongates in response to the direction of light and gravity. On the other hand, cytokinins causes lateral growth, wherein the diameter size of a cell increases.

When trees grow taller, there is a presence of auxins in its apical meristem. Once the tip is cut, the auxins go away with it. Since auxins inhibit lateral growth, their absence produces lateral buds which eventually form into side branches. If you cut the tip of a plant more often, the auxins are lessened; therefore, a plant will grow laterally.

The plant hormone **auxin** is responsible for the promotion of cell division that causes elongation in the cells of the plant. It initiates the growth of stems when it is present in high concentrations. Auxin plays a role in the maintenance of apical dominance since the **auxin moves to the darker side of the plant which will result in the cells present there growing longer than others**.