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Pollen tube. SEM image of pollen tubes growing from lily pollen grains. A pollen tube is a tubular structure produced by the male gametophyte of seed plants when it germinates. Pollen tube elongation is an integral stage in the plant life cycle. The pollen tube acts as a conduit to transport the male gamete cells from the pollen grain —either ...
Pollination. Pollination is the transfer of pollen from an anther of a plant to the stigma of a plant, later enabling fertilisation and the production of seeds. [1] Pollinating agents can be animals such as insects, for example beetles or butterflies; birds, and bats; water; wind; and even plants themselves.
Pollen tube diagram. Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. [ 1 ] It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells).
List of pollen sources. Bee collecting pollen from rata. Pollen-laden bees at hive entrance. Bee on plum tree with pollen. The term pollen source is often used in the context of beekeeping and refers to flowering plants as a source of pollen for bees or other insects. Bees collect pollen as a protein source to raise their brood.
The pollen is carried to the pistil of another flower, by wind or animal pollinators, and deposited on the stigma. As the pollen grain germinates, the tube cell produces the pollen tube, which elongates and extends down the long style of the carpel and into the ovary, where its sperm cells are released in the megagametophyte.
A pollinator is an animal that moves pollen from the male anther of a flower to the female stigma of a flower. [1] This helps to bring about fertilization of the ovules in the flower by the male gametes from the pollen grains. Insects are the major pollinators of most plants, and insect pollinators include all families of bees and most families ...
The pollen tube is produced by the single vegetative cell in the pollen grain, which passes its cytoplasm, nucleus and two sperm cells into the tube. The tube extends itself at the apex only, in an actin polymerization dependent process, and the direction in which the apex progresses responds to cyclic AMP levels, including cAMP cyclization by ...
After the pollen tube enters the gametophyte, the pollen tube nucleus disintegrates and the two sperm cells are released; one of the two sperm cells fertilises the egg cell (at the bottom of the gametophyte near the micropyle), forming a diploid (2n) zygote. This is the point when fertilisation actually occurs; pollination and fertilisation are ...