Answer:
One key way by which species evolve over time in response to changes in environmental conditions is adaptation by natural selection acting over generations. Characteristics that aid in effective survival and reproduction in the new environment grow more prevalent, while those that do not become less prevalent.
Explanation:
<span> LOOK up Negative Regulations E. Coil
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Coughing can be a symptom along with shortness of breath
Viruses reproduce by inserting their genetic code into the genetic code of a cell, from there, an active virus will copy itself over and over until that cell bursts, where the new viruses can repeat the process. Another type of virus inserts itself into the genetic code, but does not actively reproduce. It sits and waits for the cell to reproduce for it, by splitting in the way cells do.