All living organism are composed with cells.
New cells come by cell division .
Cell can - grow, divide ,produce proteins ,multiply .
Cells also store data of the organism in a molecule .
It is called DNA, in 1/2 gram of DNA the whole youtube can be stored .
DNA control how a organism looks and function .
When the cell divide in to two the DNA will be copped to the new cell .
But some time a change will come and that cause mutation .
Mutation will change the characteristic of an organism .
This mutation will be favorable or unfavorable for the organism.
This is called natural selection .
This the key mechanism of evolution
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