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Gymnosperm Roots (Ginkgo)

DicotPrimRootTriarch.jpg (21251 bytes)

GinkgoRoot240Lab.jpg (36501 bytes)
Note the Triarch Xylem organization in the primary xylem of the Image above.

Locate this in the adjacent images of Ginkgo roots. Ginkgo is a gymnosperm which has  secondary growth in its roots.

Locate the Secondary Xylem.

 GinkgoRoot.jpg (58614 bytes)

Also note the presence of a Periderm.

Pinus Roots

PineHalfSecRootXS300Lab.jpg (223492 bytes) PinePrimSecRootXSPXylemLab300.jpg (170072 bytes)
Cross-sections of a Pinus Stem showing Primary & Secondary Xylem, the Vascular Cambium & Secondary Phloem

Podocarpus Root

PodocarpusXSLM.jpg (225230 bytes) PodoXSPolLM.jpg (454292 bytes)

Cross-sections through a Woody Podocarpus root with standard illumination (above) and polarized illumination right. Locate the Primary Xylem. Is it Diarch, Triarch ...? Locate the Secondary Phloem in the top left image.

Click here for Labeled Image!

 PodoPXPolVHM.jpg (312986 bytes)

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