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Pollination is the placement of the pollen on the stigma of the carpal. This pollen transfer can be accomplished by wind, insects, built in mechanical discharge, and man. Once the pollen lands on the stigma, a series of chemical reactions takes place allowing the pollen grain to begin producing a structure called the pollen tube. As this is happening, the generative nucleus will divide and produce 2 sperm nuclei. This pollen grain with the pollen tube and 3 nuclei is considered the mature gametophyte. The pollen tube will work its way through the style of the carpal and touch the micropyle of the ovule. Here the sperm nuclei will enter the embryo sac and fertilize the egg and the two polar nuclei; hence the term double fertilization. The fertilized egg (2N) will develop into the immature seed plant, while the (3N) central cell will develop into the endosperm or food storage area of the seed.

2007-06-14 16:53:52 · answer #1 · answered by ATP-Man 7 · 0 0

Flowers have double fertilization.

1. Pollen lands on the stigma of the pistil, coming from the anther of the same flower or another flower.
2. The pollen grows a pollen tube down through the style to an ovule which is inside the ovary of the pistil. The pollen tube growth is directed by the tube nucleus.
3. The two sperm nuclei enter the ovule from the pollen tube.
4. One sperm nucleus joins with the egg nucleus to form the zygote. The zygote will develop into the embryo of the seed.
5. The other sperm nucleus joins with the two polar nuclei to form the endosperm nucleus. This nucleus directs the formation of the food storage parts of the seed.
6. The walls, or integuments, of the ovule become the seed coat.
7. The ovule forms a seed. The ovary thickens and enlarges to form the fruit.

2007-06-14 08:28:52 · answer #2 · answered by ecolink 7 · 0 0

Some flowers have both the female and male flower parts and some plants are female separate from male. Stamens of the male plant (particularly from the anther) or plant part produce the pollen for the female pistil, which is the ovary, style and stigma. Pollen transfers from anther to stigma and the combined male/ female material develops in the ovary to form a seed. The short and long of it.
Some flowers have them both in the same flower, some on separate plants like the holly (Ilex sp.) which are male and female. Some trees have male flowers on one part and female flowers on another part. When the male flowers are on the top of the tree then it can not only fertilize itself but another tree with the drift of pollen. When the female flowers are on the top though it makes it harder to self pollinate so the species relies more on pollen from another, and the drift of the pollen is more controlled.

2007-06-13 23:58:07 · answer #3 · answered by mike453683 5 · 0 0

First brewing (amalgamation, if you like) - all the base ingredients come together in a harmonious recipe, which then undergoes a mystical process (fermentation, for lack of a better word). THEN it gets distilled. And finally it gets aged, where it picks up sweet notes from the surrounding environs. I'm pretty sure I'm now in the Aging process :-) Peace to you.

2016-04-01 07:03:02 · answer #4 · answered by Anonymous · 0 0

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