Video Transcript
Use the terms “sources” and “sinks”
to complete the following sentence. Translocation is primarily the
movement of sugars from blank to blank.
You may recall that plants produce
sugars in the form of glucose during photosynthesis. Photosynthesis predominantly takes
place in the leaves of plants. But the sugars that are produced
are needed by all parts of the plant for processes such as cellular respiration, the
building of strong cell walls, and for storage. These sugars therefore need to be
transported around the plant. And they do this through a process
called translocation.
Any part of a plant which produces
or releases sugars for translocation is known as a source. And a sink is any part of the plant
that these sugars are transported to. Although we often think of
photosynthesis in the leaves as the source and storage in the roots as the sink,
this is mainly the case in the summer months when the plant is receiving lots of
light energy. In the winter, when there’s far
less light available to the plant, stored sugars in the roots will become the
source, and respiring organs, such as the leaves, assuming they’ve been retained
through the winter, will become the sink.
Now we can answer the question. The completed sentence would be
“Translocation is primarily the movement of sugars from sources to sinks.”