The sucrose is transported around the plant in phloem vessels. It needs to be able to reach all cells in the plant so that the sucrose can be converted back into glucose for respiration. The movement of sucrose and other substances like amino acids around a plant is called translocation .
Belowground organs of plants (e.g. roots and rhizomes) are sinks during plant growth since they cannot perform photosynthesis. Some organs are both a source and sink. Leaves are sinks when growing and sources when photosynthesizing
