GAMETE TRANSFER ●In majority of organisms, male gametes a | .
GAMETE TRANSFER
●In majority of organisms, male gametes are motile and females gametes are non-motile, except in fungi and algae in which both gametes are motile.
● In simple plants like algae, fungi, bryophytes and pteridophytes water is the medium through which male and female gametes moves.
●The number of male gametes are much more than number of female gametes as most of male gametes fail to reach the female gametes.
● In higher plants pollen grains are carrier of male gametes and ovule has eggs. ● Pollen grains must be transferred from anther to stigma to facilitate fertilisation.
● The transfer of pollen grains from anther to stigma is called pollination.
★Pollination may be self (anther to stigma of same flower) or cross (anther to stigma of different flower).
★Pollen grains germinate on stigma to produce pollen tube that delivers the male gametes near the ovule.
■FERTILISATION ■– The fusion of male and female gamete is called fertilization or syngamy. ★It results in the formation of diploid zygote.
★The process of development of new organisms without fertilisation of female gametes is called parthenogenesis.
