Pine trees and ferns move sugar food around in long, pointy cells called sieve cells. They are an older, simpler kind of sugar pipe.
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The phloem (say it: FLOW-em) is the plant's food pipe system. In pine trees, other cone trees, and ferns, the phloem is made of sieve cells.
A sieve cell is long and thin, with pointy ends that overlap with the next cell. Its walls have patches of tiny holes called sieve areas. Sieve cells are alive, but they have no nucleus.
Press Cut it open on the 3D model to see inside the sieve cells.
Pine needles make sugar from sunlight. Sieve cells carry that sugar to places that need food, like the roots and new growing tips.
The sugary sap passes from one sieve cell to the next through the sieve areas where their ends overlap. Since a sieve cell has no nucleus, a helper called an albuminous cell sits nearby and helps keep it working.
Press Send sugar to watch sugar pass between the sieve cells.
Flowering plants have a newer kind of sugar pipe with big holes at the ends. Sieve cells are the older design, and pine trees have used it for millions of years.