Phloem is a complex tissue which always includes sieve elements. Phloem transports photosynthate around the plant. Phloem with sieve-tube elements, as found in flowering plants, always has companion cells. The phloem of conifers with sieve cells always has albuninous cells. Other cell tyes found in phloem include parenchyma and fibers.

• Link to image of a cross section of Medicago stem showing the detail of a vascular bundle. Xylem is towards the inside, and phloem is towards the outside.
• Link to image of a cross section of Medicago stem showing the detail of the phloem consisting of sieve-tube elements, companion cells, parenchyma cells and fibers.
• Link to image of a cross section of Cucurbita stem showing sieve-tube element and companion cell.
• Link to image of a longitudinal section of Cucurbita stem showing sieve-tube elements.
• Link to image of a longitudinal section of Cucurbita stem showing a companion cell.