Fertilisation
In the previous section, the process of pollination was covered. Pollination occurs when pollen from the anther of a flower was transferred to the stigma of another flower.
Once the pollen reaches the stigma, the process of fertilisation can begin:-
Once fertilisation has occurred, the flower changes completely. The ovary swells in size to form a fruit and the fertilised ovule becomes a seed.
Seed Dispersal
Once a seed has formed, it must by scattered as far as possible from its parent plant. If the seeds were not scattered far, the seeds would have to compete with the parent plant for light and nutrients. By scattering the seeds over a large area, the seeds have a much better chance of growing.
The diagram below, shows examples of the four main types of seed dispersal:-
There are four types of seed dispersal:-
Wind - The seeds are very light and can have 'wings' or 'sails' to help the wind carry them.
Water - The seeds are held within a fruit that can float on water. These fruit trap air within them, to make them more buoyant.
Animal - The fruit has a sweet taste when eaten, the seeds pass through the animal and are deposited in droppings. Some seeds are covered in hooks which get caught in an animal's coat to be carried.
Explosion - The fruit bursts open, propelling the seeds away.
Germination
Once the seed has been dispersed, the process of germination can begin. Sometimes this can happen straight away or the seed can remain dormant for months or years before germinating.
The process of germination is the growth from a seed into a seedling (a small plant) . Germination can only start when the seed experiences the right conditions for growth. How much Water and Oxygen is available and what the temperature is, controls when germination happens.
The diagram below shows the stages of germination, from a seed to a seedling:-
The videos below show time-lapse footage of plant growth.
Seed Germinating to a Seedling
Seedling to Flowering Plant
