Pine stem. Polarised light micrograph of a section through a single annual growth ring in the stem of a pine (Pinus sp.) tree,showing xylem tissue. The large thin-walled tracheid cells (blue) are of younger spring wood,whilst smaller thick-walled tracheid cells (yellow-orange) are of older autumn wood. There are thin files of parenchyma and tracheid cells (yellow-brown) of the subsidiary medullary rays,which pass food substances radially. Many of the tracheid cell walls have bordered pits (oval,yellow-brown) that pass water and minerals side-ways. Magnification: x32 when printed 10 centimetres wide | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Wheeler, Dr. Keith |
Bildgröße: | 5125 px × 3417 px |
Modell-Rechte: | nicht erforderlich |
Restrictions: | - |