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प्रश्न
What is triple fusion?
उत्तर
After entering one of the synergids, the pollen tube releases the two male gametes into the cytoplasm of the synergid. One of the male gametes moves towards the egg cell and fuses with its nucleus, thus completing the syngamy. This results in the formation of a diploid cell, the zygote. The other male gamete moves towards the two polar nuclei located in the central cell and fuses with them to produce a triploid primary endosperm nucleus (PEN). As this involves the fusion of three haploid nuclei, it is termed triple fusion.
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संबंधित प्रश्न
What is double fertilisation? Describe the process in brief.
'Formation of primary endosperm nucleus is called triple fusion'. Give reason
Why do you think the zygote is dormant for sometime in a fertilised ovule?
Triple Fusion involves:
(i) Fusion of one male, gamete with female gamete
(ii) Fusion of tube nucleus with generative nvcleus
(iii) Fusion of two polar nuclei.
(iv) Fusion of second male gamete with two polar nuclei
What happens to the following after fertilization?
Stamens
What is the function of the pollen tube? Explain it with the help of a diagram.
Given ahead is a diagrammatic sketch of the sectional view of a germinating pollen grain. Study the same and then answer the question that follows:
Where does the germination of the pollen grain take place and how?
Given ahead is a diagrammatic sketch of the sectional view of a germinating pollen grain. Study the same and then answer the question that follows:
What is the function of the part labelled '4'?
Define fertilization.
Describe the process of double fertilization.
After fertilization the ovule becomes ______.
Pollen tube was discovered by
Male gametes in angiosperms are formed by the division of ______.
Which of the following represent megagametophyte
Caruncle develops from
In majority of plants pollen is liberated at
Write a short note on Heterostyly.
Give a concise account of the steps involved in the fertilization of an angiosperm plant.
Explain the development of a Dicot embryo
Pollen tube was discovered by
Due to which of the following reasons the pollen tube usually grows down towards the egg?
In angiosperms, for formation of which of the following triple fusion is necessary?
By which of the following double fertilization is exhibited?
Through which route the pollen tube can enter the ovule?
Double fertilization was first discovered by Nawaschin (1898) in ______.
In a fertilised embryo sac, the haploid, diploid, and triploid structures are ______.
Double fertilization is fusion of ______.
In ______ sepal is seen on the fruit after fertilization.
Find out the CORRECT sequence of events taking place in pollen - pistil interaction.
- Pollen tube enters one of the synergids and bursts to release male gametes.
- Pollen tube enters the ovule through the micropyle of the ovary.
- The pollen tube grows through the stigmatic tissue and then style.
- Pistil recognizes the correct pollen and accepts it.
All the events from pollen deposition on the stigma until pollen tubes enter the ovules are together referred to as ______.
In the figure given below label the following parts: male gametes, egg cell, polar nuclei, synergid and pollen tube
Select the option that shows the correctly identified 'U', 'X', 'Y' and 'Z' in a developing dicot embryo.
What is Siphonogamy?
Give a term for the following:
Fusion of male gamete and secondary nucleus in angiosperms.
