Difference between the unfertilised egg and fertilisation

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​ Please find below the solution to the asked query                                

​The egg that is not fertilized is known as unfertilized egg.

Fertilization is the fusion of the male and the female gametes with each other to give rise to a single-celled zygote. 

In flowering plants during fertilization, pollens from male flower are dropped on the stigma of female flower. Inside the pollen grain, two pollen nuclei (male gametes) are formed which gradually enter inside the ovule through pollen tubes. In the ovule one male nucleus fuses with the egg cell (which was lying unfertilised) to form zygote and other fuses with the secondary nucleus or the central nucleus to form the endosperm.

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