Answer:
Pandemics occur for two reasons. The first is a change in the infectious agent and the second is in human patterns. Both involve exposing people to agents they don’t have resistance to. Diseases like SARS, avian flu, and the famous Spanish flu all involved a mutation in the virus that resulted in a new disease that no one had resistance too. Examples of the second are when new groups of humans make contact, like small pox amongst native Americans, and possibly the black death.
Explanation:
Answer:
<h3>A</h3><h3>Tree roots anchor soil in place,preventing runoff. </h3>
Explanation:
<h3>I hope l helped you. </h3><h3>Please follow me. ❤❤❤</h3>
Thomas Hunt Morgan, who studied fruit flies, provided the first strong confirmation of the chromosome theory. Morgan discovered a mutation that affected fly eye color. ... Based on the inheritance pattern, Morgan concluded that the eye color gene must be located on the X chromosome.
<span> It is 130/90 or 140/90 </span>mmHg<span>. for every </span>
