Sweet pea stem. Light micrograph of a transverse section through the stem of a perennial sweet pea (Salicornia europaea) plant. The stem has evolved two green wings (left and right) to increase photosynthesis. These wings contain spongy mesophyll (pink),similar to a leaf,and several small vascular bundles (dark spots). The main stem has a ring of collateral vascular bundles (dark pink blobs) each with an outer layer of supporting fibres (sclerenchyma,green-orange-blue). Under this are phloem sieve tubes (pink),metaxylem (large vessels,brownish-red),and protoxylem (small vessels,pink). Most of the pith parenchyma has broken down leaving a hollow stem (white,centre). Magnification: x14 when printed 10 centimetres wide | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Wheeler, Dr. Keith |
Bildgröße: | 6124 px × 3464 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |