Double fertilization was first discovered by Nawaschin $(1898)$ in

The following figure shows a mature embryo sac. Where do the male gametes fuse?

The product formed by the fusion of polar nuclei and a male gamete is called.........

The phenomenon of syngamy (fertilization) in angiosperms was discovered by

In angiosperms,the process of double fertilization required to initiate the development of endosperm involves:

Differentiate between the following:
$(i)$ Red algae and brown algae
$(ii)$ Liverworts and moss
$(iii)$ Homosporous and heterosporous pteridophytes
$(iv)$ Syngamy and triple fusion