3.4 Plant Fertilisation

1. A tube begins to grow into the stigma from the pollen grain as they germinate. Pollen tubes only grow completely if the pollens are of the same species.
2. Pollen tubes grow all the way down into the ovule.
3. The male nucleus travels down this tube into the ovule.
4. This causes the pollen nucleus to fertilise with the ovule, producing a zycote and as time progresses the zycote turns into the embryonic plant.
5. The outside of the ovule forms the Testa which is the seedcoat.
6. The joining of the nucleus and ovule also produce cotelydons, which acts as a food storage for the seedlings. It is used until the plant grows its first set of leaves.
7. Then the walls of the ovaries thicken through the help of protein and sugars which the plant provides. The plants put a lot of enrgy into thickening the walls of the ovary. This leads to the growth of fruit from the walls of the ovary, also known as the carpel.

These are the things that occur after the nucleus travels down into the ovule.