why phloem movement is bidirectional not unidirectional
why phloem movement is bidirectional not unidirectional
The phloem transport depends on source - sink relationship. Therefore, the movement of phloem sap is bi directional.
More to know:
During the growth of a plant, the leaves act as the source of food as they carry out photosynthesis. The phloem conducts the food from the source to the sink (the part of the plant requiring or storing food). During spring, this process is reversed as the food stored in the sink is mobilised toward the growing buds of the plant, through the phloem. Thus, the movement of food in the phloem is bidirectional (i.e., upward and downward).
The transport of water in the xylem takes place only from the roots to the leaves. Therefore, the movement of water and nutrients in the xylem is unidirectional. Upward movement of water and minerals in the xylem depends on transpiration. Therefore it is always unidirectional.
The phloem transport depends on source - sink relationship. Therefore, the movement of phloem sap is bi directional.
More to know:
During the growth of a plant, the leaves act as the source of food as they carry out photosynthesis. The phloem conducts the food from the source to the sink (the part of the plant requiring or storing food). During spring, this process is reversed as the food stored in the sink is mobilised toward the growing buds of the plant, through the phloem. Thus, the movement of food in the phloem is bidirectional (i.e., upward and downward).
The transport of water in the xylem takes place only from the roots to the leaves. Therefore, the movement of water and nutrients in the xylem is unidirectional. Upward movement of water and minerals in the xylem depends on transpiration. Therefore it is always unidirectional.
