Advertisements
Advertisements
प्रश्न
Explain the events upto double fertilisation after the pollen tube enters one of the synergids in an ovule of an angiosperm.
Advertisements
उत्तर
The events which occur during double fertilization are:
-
Two male gametes are released by the pollen tube into the cytoplasm of synergid.
-
One of these male gametes moves towards the egg cell and fuses with the nucleus. This process is called syngamy and results in the formation of a diploid cell, zygote,which eventually forms an embryo.
-
The other male gamete moves towards the polar nuclei located in the central cell and fuses with them to form a triploid primary endosperm nucleus (PEN). This process is called triple fusion.
-
Since two types of fusion, syngamy and triple fusion, take place here, the phenomenon is called double fertilisation.
APPEARS IN
संबंधित प्रश्न
Read the statement and answer the questions that follow.
A flower of brinjal has 520 ovules in its ovary. However, it produces a fruit with only 480 viable seeds.
(a) What could have prevented the rest of the 40 ovules from maturing into viable seeds? Explain giving a reason.
(b) Describe the development of a dicot embryo in a viable seed.
(c) Why certain angiospermic seed albuminous while others are exalbuminous? Explain.
Give an example of an angiosperm seed that has a perisperm. Name the part the perisperm develops from.
Name a plant which flowers every twelve years.
Sketch and label ‘structure of a pea flower’.
A typical flower has ______ different kinds of whorl.
Angiosperms have dominated the land flora primarily because of their ______.
Which of the following statement is incorrect?
In angiosperms, the site of sexual reproduction is ______.
A flower is biologically defined as a modified and compressed _______.
What is the main function of the corolla?
