<span>Atoms that have filled outermost energy levels and do not participate in chemical bonding are called Inert Atoms. Remember this by thinking of the definition of Inert; meaning unable or not having the strength to move. So if it an atom has a filled outer level the electrons will be inert.
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The last option is corrrect because when one species move away from an environment or die it lead to decrease in biodiversity as well as the overall health of ecosystem also decreases.
Different combinations of genes in the nucleus
A) Virus.
Viruses force host cells to produce thousands of copies of the virus by attaching to the the host cell and transmitting its genetic material into it