Answer:
If the petri plates are kept open for the longer duration of time then there are chances of cross contamination.
The contamination can be defined as growth of undesired microbes in the petri dishes or tubes which is no longer useful for the experiment.
The tube if kept open will develop the growth of contaminants in it. It can be cross contamination as well.
To avoid contamination the tubes and dishes should not be kept open for a longer duration of time.
<span>Subunits of nucleic acids are called nucleotides.</span>
I think it is hydrolysis, because hydro means water and olysis means to break apart.
On early earth, the one that was referred to as "Primordial Soup" is : B. The combination of organic compounds in warm salty water
Many speculated that these organic compounds mutated and evolved into a single cell organism, which became the origin of the organisms on earth
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