Question

In animals there are special glands secreting hormones, whereas there are no glands in plants. Where are plant hormones formed? How are the hormones translocated to the site of activity?

Answer 1

Phytohormones:

Plant growth regulators take part in the growth of the plant. They are of two major types:

• Plant growth promoters like auxins, gibberellins and cytokinins.
• Plant growth inhibitors like abscisic acid.

Region of phytohormones synthesis​:

In plants, different hormones are produced by different tissues as follows:

Phytohormones	Region of synthesis
Auxin	Growing apices of shoot and root
Giberellin	Germinating seedlings
Cytokinin	Root apices, developing shoot buds, young fruits and meristematic regions

Translocation of phytohormones:

These growth regulators are translocated through the vascular system (xylem and phloem) to various parts of the plant.