Scientists Say: Phloem

This is the part of a plant’s vascular system that distributes food made in the leaves

Phloem is tissue that delivers food, made in a plant’s leaves during photosynthesis, to the rest of the plant. This tissue is part of the plant’s vascular system, which can be seen in the veins on leaves.

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Phloem (noun, “FLOH-em)

Phloem is a type of plant tissue. This tissue distributes sugars that leaves make during photosynthesis to the rest of the plant. These sugars are the plant’s food. And just like people can overeat, plants can make more sugars than they need at a certain time. When this happens, plants can stash excess food in storage organs, such as roots or bulbs. Carrots (roots) and onions (bulbs) are both examples of plant storage organs. Phloem can also carry sugars from storage organs to parts of a plant that need energy to grow.

The process of moving food around through phloem is known as translocation. Phloem’s partner in crime is xylem. Xylem is plant tissue that brings water and nutrients up from the roots to the rest of the plant. Together, phloem and xylem make up a plant’s vascular system. You can see this system at work in the veins on plant leaves.

In a sentence

Extra phloem tissue that carries lots of food allows some pumpkins to grow to enormous sizes.

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Maria Temming is the assistant editor at Science News for Students. She has bachelor's degrees in physics and English, and a master's in science writing.

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