Canadian pondweed leaf. Light micrograph of a section through a leaf from a Canadian pondweed (Elodea canadiensis) plant. The centre of the stem has a vascular system (blue) made up of a primitive axial strand that consists of the fusion of several vascular bundles but lacks xylem vessels. It doesn't need a strong vascular tissue because the water-pressure supports the stem and the epidermis is permeable to water and mineral salts. The cortex (outer layer) is made up aerenchyma tissue (red) with wide inter-cellar spaces for buoyancy and storing gases e.g. oxygen. The cells within the cortex are full of chloroplasts (red). Magnification: x37 when printed 10 centimetres wide | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Wheeler, Dr. Keith |
Bildgröße: | 3417 px × 5125 px |
Modell-Rechte: | nicht erforderlich |
Restrictions: | - |