
<em>The next time you wake in the middle of the night and need to make a trip to the kitchen or the restroom, cover one of your eyes with your hand before turning on any lights. You'll save the night vision (a.k.a. Sharingan) in that eye. The effect is trippy.</em>
Because their bodies tell them that they need more oxygen and so breathe faster, and try and get the oxygen their body requires and depends on.
This could be many different traits. Hair color, eye color, and height are all possible traits that would be passed down from parent to offspring.
<span>Phagocytosis of the microbes that enter the body or tissues. Also lymphocytes build specific antibodies against microbes.</span>