Search results
Results From The WOW.Com Content Network
Pollen itself is not the male gamete. [4] It is a gametophyte, something that could be considered an entire organism, which then produces the male gamete.Each pollen grain contains vegetative (non-reproductive) cells (only a single cell in most flowering plants but several in other seed plants) and a generative (reproductive) cell.
Plants that cannot fertilize themselves are called self-sterile, a condition which mandates cross-pollination for the production of offspring. [47] Cleistogamy: is self-pollination that occurs before the flower opens. The pollen is released from the anther within the flower or the pollen on the anther grows a tube down the style to the ovules.
This then allows the flowers to be more successful reproductively because the plants maximize their pollen dispersal with each bee visit, and less pollen is lost. [9] The relationship between buzz pollinated plants and bees benefits both groups and could be why poricidal anthers have been successful evolutionarily. [9]
They do not need to attract pollinators and therefore tend not to grow large, showy, or colorful flowers, and do not have nectaries, nor a noticeable scent. Because of this, plants typically have many thousands of tiny flowers which have comparatively large, feathery stigmas; to increase the chance of pollen being received.
For the plant, the pollinizer, this can be an important mechanism for sexual reproduction, as the pollinator distributes its pollen. Few flowering plants self-pollinate; some can provide their own pollen (self fertile), but require a pollinator to move the pollen; others are dependent on cross pollination from a genetically different source of ...
Honey bees are attracted to nectar and pollen from the staminate and hermaphrodite papaya flowers, but narrow tubes and deep flowers may limit the effectiveness of bees as primary pollinators. [2] Even so, pollen requirements for healthy and consistent fruit motivate growers to locate honeybees within their groves to pollinate in any capacity.
Few plants self-pollinate without the aid of pollen vectors (such as wind or insects). The mechanism is seen most often in some legumes such as peanuts. In another legume, soybeans, the flowers open and remain receptive to insect cross pollination during the day. If this is not accomplished, the flowers self-pollinate as they are closing.
The bee collects the pollen by rubbing against the anthers. The pollen collects on the hind legs, in a structure referred to as a "pollen basket". As the bee flies from flower to flower, some of the pollen grains are transferred onto the stigma of other flowers. Nectar provides the energy for bee nutrition; pollen provides the protein.