Question

The root endodermis because of the layer of suberin has the ability to actively transport ion in one direction only . Explain the above sentence and clear the role of suberin.

Answer 1

The explanation is as follows.

Suberin is highly hydrophobic and a somewhat 'rubbery' material. In roots suberin is deposited in the radial and transverse cell walls of the endodermal cells. This structure, known as the Casparian strip or Casparian band, functions to prevent water and nutrients taken up by the root from entering the stele through the apoplast. Instead, water must bypass the endodermis via the symplast. This allows the plant to select the solutes that passes further into the plant. It thus forms an important barrier to harmful solutes. For example, mangroves use suberin to minimize salt intake from their littoral habitat.
So in this way it allows a unidirectional transportation.

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