Question:
In a plant, translocation in the xylem is unidirectional while in phloem it is
bidirectional. Explain.
Solution:
The vascular bundle, phloem is responsible for conducting the food from the source to the sink. But the process is reversed during seasons like spring because during
that term the food which is stored in the sink is then supplied to the growing parts of the plant. The source and sink relation are hence variable so the direction of
movement of food via the phloem can be either upwards or downwards i.e. bidirectional.