You have learned that the fusion of egg and sperm produces a zygote. But how does the sperm reach the egg, and how does the zygo
te develop into a seed, which eventually germinates and grows into a mature sporophyte? In this activity, you will demonstrate your understanding of double fertilization and seed development in angiosperms. Drag the statements to their appropriate locations on the flowchart of pollination, fertilization, and seed development.
two sperm are discharged to them female gametophyte
sperm fuse with the egg and two polar nuclei
zygote forms and divides into a terminal cell and a basal cell
cells of embryo differentiate into three tissue types---- seed dries out and becomes dormant.
B)
During pollination, a pollen grain is transferred from an anther to a stigma. Once the pollen grain lands on a suitable stigma, it germinates and forms a pollen tube, a structure that grows down through the style to the ovary.
Once in the pollen tube, the generative cell from the pollen grain divides by mitosis, forming two sperm. The sperm travel down the pollen tube and are discharged into the female gametophyte. In a process called double fertilization, one sperm fertilizes the egg, forming the zygote; the other sperm fuses with two polar nuclei in the female gametophyte, forming a triploid (3n) nucleus. The zygote develops into the plant embryo, and the triploid nucleus divides and gives rise to the endosperm. Double fertilization prevents the waste of the plant's resources by ensuring that the nutrient-rich endosperm only develops if the egg is fertilized.
After double fertilization, the ovule starts to develop into a seed containing the plant embryo. As the embryo develops, the three tissue systems are established, and the cotyledons (seed leaves) form. The seeds of many species dry out as they mature. These dry seeds lie dormant until suitable germination conditions occur.
First of all, only hermaphrodites can produce offspring by themselves, and most of the time, they end up being genetically mutated, but either way it is called asexual reproduction
<span>For the answer to the question above, I'll just complete the sentence for the answer to your question. "Radial" are characteristics of downcutting streams and a youthful stage of valley evolution. I hope my answer helped you in someways </span>