Pollen tube tubes. The presence of multiple grains of pollen has been observed to stimulate quicker pollen tube growth in some plants. The vegetative cell then produces the pollen tube, a tubular protrusion from the pollen grain, which carries the sperm cells within its cytoplasm. The sperm cells are the male gametes that will join with the egg cell and the central cell in double fertilization. The germinated pollen tube must then drill its way through the nutrient-rich style and curl to the bottom of the ovary to reach the ovule. Once the pollen tube reaches an ovule, it bursts to deliver
Anti-scratch coating cloth. Anti-scratch coating An anti-scratch or scratch-resistant coating is a film or coating that can be applied to optical surfaces, such as the faces of a lens or photographic film, intended to mitigate scratch effects. Anti-scratch coating does not interfere with how the lens functions and does not affect vision, but creates a permanent bond with the lens that reduces the appearance of hairline scratches which is common to eyeglass lenses. Although an anti-scratch coating is not 100% scratch-proof, it helps to prevent minor scratches that can easily happen to a regular lens. These minor scratches can damage the surface