Explain the process of gamete transfer.

(N/A) After the formation of male and female gametes,they must be brought together to facilitate the process of fertilization.
In the majority of organisms,the male gamete is motile and the female gamete is non-motile. The male gamete requires a medium to travel.
In algae,bryophytes,and pteridophytes,the male gamete travels through a water medium.
$A$ large number of male gametes,however,fail to reach the female gamete.
To compensate for this loss of male gametes during their travel,the number of male gametes produced is several thousand times higher than the number of female gametes produced.
In angiosperms,pollen grains are the carriers of male gametes,and the ovule contains the egg cell.
- Pollen grains are produced in anthers and transferred to the stigma through a process called pollination.
- This process involves external agents like water,air,insects,birds,etc.
Pollen grains germinate on the stigma,and the pollen tube carrying the male gametes reaches the ovule and discharges two male gametes near the egg cell.
In bisexual animals,since male and female gametes are formed in different individuals (or even in the same individual),the organism must evolve a special mechanism for gamete transfer,which is a prerequisite for fertilization.