Pine stem. 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 (white-brown) are of younger spring wood (right of image),whilst smaller thick-walled tracheid cells (also white-brown) are of older autumn wood (left of image). There are thin files of parenchyma and tracheid cells (yellow-white) of the subsidiary medullary rays,which pass food substances radially. Many of the tracheid cell walls have bordered pits (circles) that pass water and minerals side-ways. Magnification: x37 when printed 10 centimetres wide | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Wheeler, Dr. Keith |
Bildgröße: | 5125 px × 3417 px |
Modell-Rechte: | nicht erforderlich |
Restrictions: | - |