Mechanism of Translocation in the phloem
Though several theories have been advanced, none of them completely explain the mechanism of phloem conduction. Munch’s (1930) theory is the most compelling of the groups. The following are the main steps in the mass flow theory:
- Gropup’s pressure flow or mass flow hypothesis.
- This recognized mechanism is used to move sugars from source to sink.
- Sucrose is produced from glucose at the source.
- Sugar is transported by active transport in the form of sucrose into companion cells and then into sieve tube cells. This is the process of loading the source.
Phloem Transport
In plants, transportation is an important process. From roots to the tips of their leaves, plants carry the water and nutrients which are required to survive. The water and minerals are transported in plants by:
- Phloem
- Xylem
Xylem and phloem tissues are present all over the plants. These conducting tissues grow from the roots of trees and ascend through the trunks. Like spider webs, they eventually branch off into the branches and spread even more into every leaf.