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
Resistant starch manufactured foods. Starches with high amylose content generally have increased resistant starch. Resistant starch (RS) is any starch or starch digestion products that are not digested and absorbed in the stomach or small intestine and pass on to the large intestine. RS has been categorized into four types: Processing may affect the natural resistant starch content of foods. In general, processes that break down structural barriers to digestion reduce resistant starch content, with greater reductions resulting from processing. Whole grain wheat may contain as high as 14% resistant starch, while milled wheat flour may contain only 2%. Resistant starch content