Answer:
Pollen is carried by external agents such as wind, and animals(especially insects).
Step-by-step explanation:
In flowering plants, most flower is the reproductive organ. It bears the stamen that produce the pollen grains, and the pistil which contains the ovule in the ovary.
The pollen are carried by external agents to the stigma of the pistil. Then the pollen then develops a tube that leads to the egg cell on the ovary. A tube cell leads the male gamete which are carried in the tube passively. Fertilization occurs when one of the male gamete fuses with egg cell to form a zygote. The fertilized ovule develops into a seed, while the ovary develops into a fruit.