Translocation
Moving food around (Supplement)
- Leaves make sugar, but the whole plant needs it.
- Translocation moves sucrose and amino acids in the phloem.
- It carries them from sources to sinks.
Practice
Translocation is the movement of:
Translocation moves sucrose and amino acids through the phloem.
Sources and sinks
- Sources release sucrose or amino acids — e.g. the leaves, which make sugar by photosynthesis.
- Sinks use or store them — e.g. growing roots, or a storage organ.
- The direction can change: a potato is a sink when it fills up in summer, but a source in spring when it sprouts.
Practice
A "source" in translocation is a part that:
A source releases sugar (e.g. leaves making it); a sink uses or stores it.
Practice
A storage organ can act as a sink at one time of year and a source at another.
The direction of translocation can change — e.g. a potato stores sugar (sink), then releases it when sprouting (source).
You've got it
Key idea
- translocation = movement of sucrose + amino acids in the phloem (Supplement)
- from sources (make/store, e.g. leaves) to sinks (use/store, e.g. growing roots)
- the direction can change with the season