Xylem in a cross section of Cucurbita stem - prepared slide 100x objective

Photographer

Clayton, Michael W.

Summary

• Photomicrograph
• Xylem is a complex tissue with a number of different types of cells. In Cucurbita we find vessel elements and parenchyma cells. Vessel elements are a type of tracheary element. They differ from tracheids in that they have perforations. Perforations are areas where both the primary and secondary walls are absent and water moves freely between vessel elements. Tracheids only have pits. These are areas where the secondary wall is absent put where the primary wall is intact. Water moves from tracheid to tracheid only by passing through the primary walls at the pits.