The figure shows the L.S of ovary at the time of fertilisation. Define triple fusion.

The generative cell of the pollen of angiosperms divides and forms two male gametes during the growth of pollen tube into the stigma. The first male gamete fuses with the egg cell and forms a zygote. Second male gamete fuses with two polar nuclei to form a triploid Primary Endosperm Nucleus (PEN). This is called triple fusion. Since, two fusions, i.e. syngamy and triple fusion occur in an embryo sac, this is called double fertilisation. Central cell and primary endosperm nucleus called as Primary Endosperm Cell (PEC) develops into the endosperm and zygote develops into an embryo.

The figure shows the L.S of ovary at the time of fertilisation. What happens to the part F and G.

According to the diagram, F is Egg cell and G is Polar nuclei. One of the two sperm cells fertilizes the egg cell, forming a diploid zygote and the other sperm fuses with the two polar nuclei, forming a triploid cell that develops into the endosperm. Together, these two fertilization events in angiosperms are known as double fertilization.

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Anamika Tripathi and Sanubia Solutions for Chapter: Pollination and Fertilisation, Exercise 1: Check point

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Anamika Tripathi Biology Solutions for Exercise - Anamika Tripathi and Sanubia Solutions for Chapter: Pollination and Fertilisation, Exercise 1: Check point

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