Describe double fertilization in angiosperms.

Describe double fertilization in angiosperms.
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Ans: Occurrence of two types of fertilizations in the same embryosac is called as double fertilization. It was discovered by Nawaschin in Fritillaria and Lilium. It is a feature of angiosperms.

The two fertilizations are Syngamy and Triple fusion.

Syngamy: It is fusion of one of the male gametes with the egg cell to form zygote. It is also known as true fertilization or zygotic fertilization. It was discovered by Strasburger in Polygonum.

Triple fusion: It is fusion of second male gamete with the diploid secondary nucleus or two haploid polar nuclei to form triploid Primary Endosperm Nucleus. It was discovered by Nawaschin in Fritillaria and Lilium. PEN develops into endosperm. 


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