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PLANT FERTILIZATION. “Compared with the animal kingdom, fertilization is particularly complex in flowering plants (angiosperms). Sperm cells of angiosperms have lost their motility and require transportation as a passive cargo by the pollen tube cell to the egg apparatus (egg cell and accessory synergid cells).” http://www.sciencedirect.com/science/article/pii/S0960982215015584 View in LinkedIn

EVOLUTION. Herbert Spencer "defined evolution as "a change from an incoherent homogeneity to a coherent heterogeneity". https://lnkd.in/dMvAeqz View in LinkedIn

DOUBLE FERTILIZATION IN PLANTS (Dr Larry Jensen). A superb primer. Brilliant work. https://youtu.be/0UEpq1W9C_E View in LinkedIn

FRAGMENT FROM NATURE contemplates the curious phenomenon of double fertilization in flowering plants, a large group of living creatures. This is a process unlike the reproduction of animals or other plants, and appears to confer no particular competitive advantage. Perhaps it is a pure happenstance of evolution, wrought by pure accident, which survived. But, just like the mating fruit-fly where the female genes become massively lit up in short order, so also, the cross-talk and molecular chatter that accompanies the pollen tube entry is very impressive. Hardly dumb sessile creatures. View in LinkedIn

NUTS AND BOLTS. “In flowering plants, the egg is intimately associated with typically six to eight other haploid cells forming the female gametophyte. These include the central cell representing the second female gamete and two synergid cells that produce the signals, which guide the male gametophyte, or pollen tube, towards the ovule. The pollen tube delivers two non-motile sperm cells whose release occurs by bursting, which in turn is triggered when the tube interacts with the synergid cells.” https://lnkd.in/dXVTT6X View in LinkedIn

RACING POLLEN TUBES. “The reproductive strategy of flowering plants is different and involves competition among growing pollen tubes to enter one ovule and to deliver their sperm cell cargo. The first pollen tube that enters an ovule usually releases its cargo and one sperm cell fuses with the egg cell forming the embryo while the second sperm cell fertilizes the central cell to generate the endosperm. Later-arriving pollen tubes do not enter already targeted ovules.” http://www.sciencedirect.com/science/article/pii/S096098221200468X View in LinkedIn

DIFFERENT SPERM COMPETITION. “Sperm competition does not occur in flowering plants as typically only a single pair of sperm cells is delivered for double fertilization. Two recent reports show that plants are capable of avoiding reproductive failure when defective sperm cells are released.” http://www.sciencedirect.com/science/article/pii/S096098221200468X View in LinkedIn

SPERM COMPETITION. “In vertebrate and invertebrate species millions of sperm cells compete for fertilization with the ova or egg cell. Usually the largest, longest, fastest and physiologically most active sperm cells win the race and defective sperm cells are sorted out. Sperm competition thus represents a powerful selective force to guarantee fertilization and reproductive success.” https://lnkd.in/dhgWbCC View in LinkedIn

POLLEN GRAINS. “The complexity of crosstalk during this journey, associated with self- and non-self-recognition mechanisms, represents not only a major driving force of speciation, but also an exciting and challenging area to investigate the function and evolution of intercellular communication mechanisms in plants.” http://www.sciencedirect.com/science/article/pii/S1674205214608996 View in LinkedIn

SPACESHIPS. “Pollen grains can be transported over long distances by wind or animal pollinators, are mostly tolerant of desiccation, and are capable of generating a long tube that grows deeply into the maternal tissues of the ovary that harbor the protected female gametes (egg and central cell). These structural innovations likely exerted a significant influence on the evolution of communication mechanisms in sexual reproduction.” http://www.sciencedirect.com/science/article/pii/S1674205214608996 View in LinkedIn