A mature potato leaf produces more sucrose than it uses. A developing tuber removes sucrose from the transport tissue to use or store it.
Explain how sucrose moves from the leaf to the tuber. Then predict the direction in which sucrose would move if the tuber later became a source and a shoot tip was growing.
80 exam-style questions on Edexcel GCSE Biology 6.2 Transport in plants, covering 6.2.1 Root hair cell adaptations, 6.2.2 Structure of xylem and phloem, 6.2.3 Transpiration and stomata, 6.2.4 Translocation of sucrose, 6.2.5 Leaf structure for photosynthesis, 6.2.6 Environmental factors on water uptake, 6.2.7 Rate calculations for transpiration, and 6.2.8 Plant adaptations to extreme environments. Each one has a worked solution and a mark scheme showing where the marks go.