Resultado de búsqueda
7 de mar. de 2017 · In rice, the pistil is the female reproductive organ, and it consists of two stigmas and an ovary. The stigma is capable of receiving pollen grains and guiding pollen tube growth. The ovary holds the embryo sac, which is fertilized with male gametes to produce seed.
A pollen grain on the stigma grows a tiny tube, all the way down the style to the ovary. This pollen tube carries a male gamete to meet a female gamete in an ovule. In a process called fertilisation, the two gametes join and their chromosomes combine, so that the fertilised cell contains a normal complement of chromosomes, with some from each ...
28 de jun. de 2008 · The pollen tube invades the stigma and grows through the style towards the ovary, where it enters an ovule, penetrates the embryo sac (female gametophyte) and releases two sperm cells, one of which fertilizes the egg, while the other fuses with the two polar nuclei of the central cell to form the triploid endosperm.
Explain cross-pollination and the ways in which it takes place. Describe the process that leads to the development of a seed. Define double fertilization. In angiosperms, pollination is defined as the placement or transfer of pollen from the anther to the stigma of the same flower or another flower.
11 de jun. de 2004 · In this review, we (1) survey recent discoveries of pollen and stigma functions both before and after they make contact, and (2) address the great diversity in pollen and stigma structures across taxa, focusing on how they accomplish key tasks in pollination.
Mature pollen grains contain two cells: a generative cell and a pollen tube cell. The generative cell is contained within the larger pollen tube cell. When a pollen grain reaches the stigma, it germinates into a pollen tube. The generative cell migrates with the pollen tube to enter the ovary.
Once a flower has been successfully pollinated and fertilized, parts of it eventually develop to form the fruit, seed, etc. Let's take a closer look at some of these structures - the endosperm, embryo, seed and fruit.
