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Viruses reproduce within the living cells of the host and use the cellular machinery to synthesize their own genome and other components. To gain entry into cells, they have developed a variety of mechanisms to introduce their genes and proteins into host cells.
Answer: If all organisms developed from a common ancestor by gradual changes, we would expect there to be organisms that have characteristics intermediate between two categories and cannot be easily classified as either.
Explanation:
Bioremediation is a branch of biotechnology that employs the use of living organisms, like microbes and bacteria, in the removal of contaminants, pollutants, and toxins from soil, water, and other environments. Bioremediation is used to clean up oil spills or contaminated groundwater.