The
flowering plants show two generations i.e. sporophyte and gametophyte,
whichalternate with one another, during life cycle.A sporophyte is a
dominant multicellular, diploid generation which is formed from zygote
or fertilized egg. This generation produces spores (microspores and
megaspores) by meiosis. The gametophyte is a small multicellular,
haploid generation, which is formed from spores. The male gametophyte
develops from microspore or pollen grain; and the female gametophyte
develops from megaspore. The male and female gametophytes produce male
and female gametes (sperms and egg) by mitosis. The gametophytes in
flowering plants are short lived, much reduced and dependent for
protection on sporophyte.
Double fertilization
The pollen tube grows via style through micropyle into the ovule.
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