3.4 Plant fertilisation

The pollen grains are on the stigma and the pollen grains germinate and the tube begins to grow and this is usually species specific so the tube will only grow if they are the same species.

The pollen grain (male nucleus) goes down through the pollen tube to the female nucleus (the ovule)
After this has occured 4 things will happen:

1. Pollen grain will fertilise the ovule ------> the formation of a zygote -------> grow into the embryo plant                                                                                                                                                   .
2. The outside of the ovule forms the testa seed coat                                                                             .
3. Inside the ovule in addition to the zygote it will also give the formation of the cotyledons. These are food stores for the seedling. This will support the seedling until it develops its first set of leaves.                                                                                                                                                          .
4. Thickening on the walls of the ovsry so the plant will put a lot of energy there so things like sugars, protein. It will buils these up to form the fruit which is developed from the wall of the ovary/carpel.