Question

Describe the mass flow hypothesis for translocation of organic solutes(food) in plants.

Answer 1

Munch's Mass Flow Hypothesis is the theory which explains the flow of food materials through the phloem from the concentration regions to lower concentration regions. The force is needed to move organic food materials downwards in the phloem. This is caused due to differences in osmotic potential. There is a turgor pressure gradient exists between the supplying and receiving tissues. The experiment was performed using two osmometers with difference in concentrations. This theory proves that there is movement of food from the leaves to roots. The leaves are the regions where the food is produced and thus, serves as the source end. The roots are the regions which require food to perform absorption and respiration. Thus, the roots serves as sink end. The flow is from the source end to sink end.