Hello. It is a very good question but it is very general because Biology covers many sub-disciplines.
In a few words biology is a natural science that study life and study all living organisms. This science can be divided in several fields fo exmaple, chemistry, physical structure, development, genetics and evolution. Biology has been used with other hard sciences like physics and astonomy to study the lyfe in other places of the universe! Then Biology is focus mainly in studying life in our planet, other plantes andthe universe.
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