Pollen transport in flowers
Pollination is the transfer of pollen containing male sex cells from the stamens of a plant to the pistil containing the eggs. Afterward a pollen tube grows through the pistil and sperm nuclei migrate to the egg where fertilization (union) takes place. The seed then develops.
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Pollen transport in trees
I need the process of pollen transport in trees.
Please help me on this question.
thank you very much.
It can be the same, although on many trees pollen serves as the mover of the pollen. Typically, fruit trees need insects to move the pollen, and genus Pinus needs wind. In my area, wind pollinates oak, pine, elm. Some nut trees (almond comes to mind) bees play an important part, others (pecan) depend on wind.
Pollen transport in trees is similar to that in flowers, although there are slight variations. Here is the process of pollen transport in trees:
1. Production of pollen: Trees produce pollen in their male reproductive organ called stamens. Each stamen consists of an anther at the tip, which produces pollen grains. These pollen grains contain the male sex cells.
2. Pollen release: When the pollen grains are mature, the anther releases them into the air.
3. Pollen dispersal: Unlike flowers, trees do not rely on pollinators such as bees or butterflies for pollen transfer. Instead, trees rely on various mechanisms for pollen dispersal, which include wind, water, or animals.
- Wind pollination: In wind-pollinated trees, such as pine or oak trees, pollen is released in large quantities and is lightweight and powdery. It is designed to be easily carried by the wind.
- Water pollination: In some aquatic trees or plants, like mangroves, pollen is released into the water. It is then carried away by currents to reach the female reproductive organs of other trees.
- Animal pollination: Although less common in trees, some species rely on animals for pollen dispersal. In these cases, trees produce showy, fragrant flowers to attract specific animal pollinators, such as birds or bats. The pollen sticks to the bodies of these animals as they visit the flowers and is transferred to other trees when the animals move on.
4. Pollen capture: Once pollen is dispersed, it needs to land on the female reproductive organ of another tree in order to achieve pollination. This organ is called the pistil, and it consists of the stigma at the top, style in the middle, and the ovary at the base.
5. Pollen tube growth: When a pollen grain lands on the stigma, it germinates and creates a pollen tube. This tube grows through the style and reaches the ovary.
6. Fertilization: The sperm nuclei within the pollen grain migrate down the pollen tube and fertilize the egg cells within the ovary. This union of the male and female sex cells results in fertilization.
7. Seed development: After fertilization, the ovary develops into a fruit, and the fertilized eggs develop into seeds. These seeds can then be dispersed, germinate, and grow into new trees.
So, in summary, pollen transport in trees involves the production of pollen in stamens, its release into the environment, dispersal by wind, water, or animals, the capture of pollen by the pistil, pollen tube growth, fertilization, and finally, seed development.