While still attached to the anther, the nucleus of the pollen grain divides, producing two nuclei, one of which becomes the tube nucleus, the other is called the generative nucleus. The generative nucleus divides again, forming two sperm cells. Once the pollen grain is released from the anther, it is transported (by wind or fauna) to the stigma of the female flower. Once a pollen grain has landed on the stigma, it begins to grow a pollen tube (there are three nuclei in the pollen tube, one from the tube nucleus, and the two sperm). When the pollen tube reaches the ovary, both sperm cells enter the ovule, one fuses with the egg nucleus, the other fuses with polar nuclei that is also inside the ovule, forming the endosperm.
The pollen grain reach the pistil either by self-pollination or by cross pollination by pollinators.
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.
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.
Pollen is the plants mechanism of transferring haploid (n) male genetic material (male gametophytes) from the anther of one flower to the stigma of another (cross-pollination) or from the anther of one flower to the stigma of the same flower (self-pollination).The pollen grain is hard and encapsulates the genetic materials (of one parent) with in, in very much the same way that a seed contains the genetic material of both parents.Pollen is small (sometimes microscopic), light and can travel far by wind or attached to insects (bees, moths, butterflies).In angiosperms pollen is produced in the anther of the flowers, in gymnosperms it is produced in the male cones of the plant.When the pollen grain lands on the stigma of suitable flower (very closely related species or same species) the pollen grain germinates; a pollen tube grows down the style and into the ovary (controlled by the generative and tube nucleus - which were contained in the pollen grain) of the flower, here it releases two sperm nuclei which fuse with the haploid (n) nucleus of the ovule to form a zygote.Pollen is made in the male part of the flower (anther) and is full of genetic material. When the pollen and the ova (egg) are joined the DNA from the pollen enters the ova and joins with its DNA. This is fertilisation and the fertilised ova grows into a seed. (pollen has a similar job to do for plants that sperm does for animals).
When they land on the style they begin to bore their way through the stigma all the way to the ovule. Through the tube made by the tube nucleus of the pollen grain: each pollen grain has two nuclei, one called generative nucleus which combines with the nuclei of the ovule, and the other called tube nucleus tube nucleus which forms a tube that penetrates the stigma till it reaches ovule then it degenerates.
When a pollen grain is immature male gametophyte, it has two cells ,a generative cell and a tube cell. A pollen grain becomes a mature male gametophyte when the generative cell divides by mitosis to form two sperm cells. In most species, this process occures after the pollen grain lands on the stigma of a carpel and the pollen tube begins to form. $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
When a pollen grain lands on stigma, pollination occurs. The pollen grain germinates and the pollen tube grows through the style. The sperm nucleus travels through the tube (generated by the tube nucleus) and fuses with an ovule which then develops into an embryo (or zygote)
When they land on the style they begin to bore their way through the stigma all the way to the ovule. Through the tube made by the tube nucleus of the pollen grain: each pollen grain has two nuclei, one called generative nucleus which combines with the nuclei of the ovule, and the other called tube nucleus tube nucleus which forms a tube that penetrates the stigma till it reaches ovule then it degenerates.
While still attached to the anther, the nucleus of the pollen grain divides, producing two nuclei, one of which becomes the tube nucleus, the other is called the generative nucleus. The generative nucleus divides again, forming two sperm cells. Once the pollen grain is released from the anther, it is transported (by wind or fauna) to the stigma of the female flower. Once a pollen grain has landed on the stigma, it begins to grow a pollen tube (there are three nuclei in the pollen tube, one from the tube nucleus, and the two sperm). When the pollen tube reaches the ovary, both sperm cells enter the ovule, one fuses with the egg nucleus, the other fuses with polar nuclei that is also inside the ovule, forming the endosperm.
No, after a research it is not seen that a pollen grain of a flower have only one lobe. Commonly pollen grain have two or three lobes.
No, sperm cells do not grow out of a pollen grain. In plants, sperm cells are produced within the pollen grain, and they are involved in fertilization when the pollen grain reaches a female reproductive structure. Each pollen grain contains two sperm cells.
The pollen grain reach the pistil either by self-pollination or by cross pollination by pollinators.
There are two things that must join to make a seed. The zygote, or embryo, must join with the ovule.
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.
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.
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.