What happens after pollen lands on the stigma of a flower? it grows a tube to travel down to the ovary. it fertilizes the plant at the stigma. it grows a tube to travel to the style. it grows a tube to travel to the petal.?

it grows a tube to travel down to the ovary

Explanation:

As a result of pollination, pollen grain lands on the sigma of the pistil or carpel.  On the stigma pollen grain begins to germinate and grows a long pollen tube.  The pollen tube grows longer and makes its way from the stigma, down the style and reaches to the ovary. Pollen tube carries two male gametes or sex cells. One male gamete fertilize the egg cell to produce zygote and the gamete fuses with polar nuclei to form primary endosperm cell.

layer 3 is younger than layer 6.