phloem: Quick Facts

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Facts

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Photos and Videos

longitudinal section through xylem and phloem

Diagram comparing xylem and phloem cells, showing labeled illustrations of a vessel member, tracheids, and fiber for xylem on the left, and a sieve element, companion cell, sieve plate, sieve areas, and fiber for phloem on the right.

A labeled diagram of a typical root cross section shows layers from the outside inward: root hairs, epidermis, cortex, endodermis, pericycle, and a central cylinder containing primary xylem and primary phloem.

stem cross section

Diagram showing various fern leaf types, including simple, once-divided, falsely dichotomous, and palmate leaves, examples of leaf venation patterns, and cross-sections of petioles illustrating internal vascular arrangements.

leaf development

See how sieve tubes and sieve plates stimulate mass flow within a plant's phloem cells

How the vascular system works in plants

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Topics

primary phloem secondary phloem phloem parenchyma sieve element P-protein mass flow companion cell sieve plate sieve area sieve-tube member xylem