ANGIOSPERMS - Group of plants having covered seeds in fruits. - Produce  flowers  having reproductive organs. - Most evolved plants. - Large no. of plants in varied habitats, small microscopic plants ( Wolfia ) to large trees. - Reproduction by vegetative and sexual methods. - In sexual reproduction pollens shed off and reach to stigma of Gynoecium by pollination. - Pollen germinates to form pollen tube with two male gametes and one tube nucleus. - One gamete fuses with egg (Syngamy) and other with secondary nucleus to form PEN (primary endosperm nucleus). The whole process is called Double fertilization. -  Zygote forms  embryo and PEN forms Endosperm  in ovule whic h changes into seed inside fruit . -  Ovary wall changes into Pericarp (fruit wall). - Alternation of generation occours.