Describe the process of double-fertilization in an angiosperm, and explain the significance of this process in plant evolution.

Question

What will be an ideal response?

Answer 1

Ans: Angiosperms go through a process called double-fertilization. Double-fertilization consists of syngamy and triple fusion. During this time, there is an embryo sac that is within an ovule. This sac contains three things: an egg cell, polar nuclei, and three antipodals. Once pollination occurs, the grain from the pollen germinated onto the stigma. The pollen tube is then formed through regenerative cells. The accessory cell will then move to the ovule. Next, the generative cell ends up dividing and forms not one, but two male gametes. Now the gamete fuses with the egg cell. This is called syngamy. The other male gamete combines with the polar nuclei. This is known as triple fusion. Both have different results. Syngamy results in the formation of an embryo. On the other hand, triple fusion results in the making of a primary endosperm nucleus. The primary endosperm nucleus is stored in the ovule. It also nourishes the embryo that is growing inside of the seed. The seeds now can be stored longer. This allows for the seeds to be more viable for a longer amount of time. Ultimately the angiosperm can successfully propagate themselves in the environment