There are only 6 days during any cycle when a women can get pregnant. the 5 days leading up to ovulation and a complete day after . This is because sperm can live up to 5 days in a women's body . So when she is ovulating it is most likely.
Using a molecular clock, scientists are able to estimate the amount of time that two species have been evolving independently.
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The answer is RNA polymerase binds to a promoter region of DNA.
