Answer:
The nucleus at the central part of the cheek cell contains DNA. When a drop of methylene blue is introduced, the nucleus is stained, which makes it stand out and be clearly seen under the microscope.
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<span>The MOSQUITO spreads more parasitic diseases to humans than any other vector.
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Ill need to know what change you predicted, but natural selection can contribute to the change by allowing the organism with the mutation (advantage or disadvantage) to either parish or aid in its survival, resulting in that mutation to be passed on the other generations through breeding