Which molecule in Diagram 11 is used to transport energy to other parts of the plant?

The answer is Sugars, or sugar molecules!

Explanation:

The sugar and other organic molecules are transported through the plant by means of a special layer of tissue called phloem. Phloem is composed of living cells that transport a water solution of sugars that we commonly call sap.

The  molecule is Sugar ,transported principally as Sucrose, but originally as Glucose after photosynthesis  and stored as starch in plants.

The sucrose is transported in the Phloem( one of the vascular tissues, the second is the xylem. They are located adjacent o each other.)The process of transportation is called, Pressure Flow Model. The process of moving the sugar through the plants is called Translocation.

There are two regions during transport of sugar in translocation. The source where the sugar is produced, that is the  green leaves, and the sink where the sugar is metabolized.

Therefore the high concentration of the sugar at the source([plant leaves) increases the solute potential of the cell in the phloem of the leaves. This set up a gradients that draw water from the adjacent  xylem into the phloem by osmosis.

The  water influx increases the pressure potential of the phloem sap, and which makes the phloem turgid. The creates turgor pressure because of the increases of the phloem sap (containing sugar).The pressure  leads to the bulk transport of the sap contain sugar (translocation) from the source( leaves) to the Sink.

At the sink, the sugar is withdraw . Thus the solute potential rises,(with a drop in pressure potential) and  water  return by osmosis back to the xylem for the process to continue with another transport.

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the answer you are looking for is the united states forest service.

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