Sunflower root. Light micrograph of a transverse section through the root of a sunflower (Helianthus annuus) plant,showing primary tissue. From outer root to centre: single layer of cork cells (brown violet); cortex of parenchyma (violet); ring and remains of the pericycle (dark violet). At the centre of the root there is no pith,but xylem primary metaxylem (centre) and protoxylem,made up of star-shaped arms (grey); next is the primary phloem,in-between the xylem,with small cells (dark-violet) and sieve tubes. Magnification: x13 when printed 10 centimetres wide | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Wheeler, Dr. Keith |
Bildgröße: | 5441 px × 3669 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |