The skeletal system since the brain is apart of the skeletal system.
Bacteria<span> are single-celled, </span>prokaryotic<span> microorganisms that exist in abundance in both living hosts and in all areas of the planet.
</span>
Lack of predators.
An abundance of Food.
<span>Roughly 5.6 years would be added to the average lifespan of the U.S. population. The test's lifespan increased from 719 to 770, or by 1.071. Multiplying the average lifespan by this amount would equal 84.609.</span>