Translocation (AQA GCSE Biology): Revision Note

Translocation

• Translocation can be defined as:

the movement of dissolved sugars through phloem tissue

• Sugars may be transported upwards or downwards in the phloem:

  • Sugars travel from the leaves to the rest of the plant when photosynthesis is taking place

  • Sugars travel from storage organs to the rest of the plant when photosynthesis is not taking place

• Sugars transported by translocation will either be used immediately by the plant or stored

• Phloem is made of tubes of elongated (long) living cells joined end to end

• The end walls between the cells have pores in them, so cell sap containing dissolved sugars can move from one phloem cell to the next

Comparing transport in the xylem and phloem