A Life Form

You can find wheat fields in the country.
One grain will be used as the seed and will return the others, but it is not so certain How many and if it occur after all.
How many - it is the first question.
The second grain will be smashed and turned into the flour and it becomes a bread or something else.
And will not multiply.
Among the wheat you can find a mouse family.
They are eating the grain so not every grain will multiply, even if the people wont't take it.
Mouses can reproduce and some of them will have their own children... some will be eaten by predators and some will just die.
And we have humans on the planet.
They are the most powerful predators on the planet so they are quite hard to be eaten by the other predators, but in common sense... They can be eaten by small life forms.
And some humans will have the children and the families. Some won't because They chose that way and some cannot because They were born that way or were made by their life or people sourounding them.
Some people will have the only Child, some will have more.
Do you see the purpose of this everything and How even the smallest life form is important to this world?
Even if we cannot see How it affects the others?