Either randomly on the wind, or when a flying insect covered in pollen brushes against the pistil as it flies from flower to flower.
ambot nimo
The reason why some pollen grains have spikes is because of the plant species. It also may be because of where the plant was adapted. Pollen grains have spikes also simply due to the location where the species is found. It is located in the coastal species where pollen grains have a different pollen shape to help with things such as salt resistant while a species found inland will be more heat resistant. It really just depends on the type of environment in which the plant has adapted. By Lyn Le
A sticky secretion on the scales of seed cones traps pollen grains. Structure is produced by a pollen grain that lands near an ovule is pollen tubes.
-pollen sticks to the stigma at the end of the pistil -pollen tubes grow down the pistil to the egg cells -sperm cells from the pollen moves down the tubes -fertilization combines DNA
Depending on the type of pollinators, the pollen grains may be sticky or light. Exine present on the pollen grains as the outermost covering layer is contributed by the tapetum cells. Reaching on the stigma after pollination, the stigmatic cells interact with the material of exine to determine the compatibility of the pollen to allow its germination for fertilization.
The pollen grain reach the pistil either by self-pollination or by cross pollination by pollinators.
ambot nimo
Pollen grains reach the pistil through pollination. The pollen grains are placed on the stigma of the carpal, and it transfers by wind, insects, built in mechanical discharge, and men. When the pollen lands on the stigma, it starts a series of chemical reactions that allow the pollen grain to produce a structure called the pollen tube. At the same time, the generative nucleus divides and produces two sperm nuclei. The pollen grain with the pollen tube and three nuclei is a mature gametophyte. The pollen tube works its way through the style of the carpal and touches the micropyte of the ovule. The sperm nuclei enter the embryo sac and fertilizes the egg and two polar nuclei, referred to as double fertilization. The fertilized egg develops into the immature seed plant, and the central cell develops into the endosperm, or food storage ares, of the seed.
i think not
I think it's Stigma -.-t
the pistil is helpful to plants it gives of hyfro chemicals whic is needed to undergo stimulation
stamen is the broad term; the individual parts are called anthers. actually i think he means the stigmata
I think that the pollen grains is neede to fertilize the carpel.......
I think that heavy rain on a fruit orchard in the spring would cause a poor fruit yield because all the pollen would be washed away, and therefore, the eggs would not be fertilized. The ovary, in which the ovules are contained, become the fruit once all the ovules are fertilized. The pollen is produced in the anther, and then they are transported to the pistil by different insects. The pistil contains the stigma, which is a sticky receptive surface where the pollen fall. The stigma also contains the style, which is the pollen tube through which the pollen reach the eggs. Now, if there is heavy rainfall, the pollen may not stick to the stigma, and then be washed away, or the insects may not come and transport the pollen to the stigma, which means that the ovary would never become a fruit.
The reason why some pollen grains have spikes is because of the plant species. It also may be because of where the plant was adapted. Pollen grains have spikes also simply due to the location where the species is found. It is located in the coastal species where pollen grains have a different pollen shape to help with things such as salt resistant while a species found inland will be more heat resistant. It really just depends on the type of environment in which the plant has adapted. By Lyn Le
A sticky secretion on the scales of seed cones traps pollen grains. Structure is produced by a pollen grain that lands near an ovule is pollen tubes.
-pollen sticks to the stigma at the end of the pistil -pollen tubes grow down the pistil to the egg cells -sperm cells from the pollen moves down the tubes -fertilization combines DNA