Natural emergency: something that occurs naturally
manmade: something caused by a person (ex.shooting)
The respiratory system can be damaged from smoke inhalation and tar buildup from the chemicals used in tobacco, which can also harm the heart and blood vessels. Two conditions that can be caused from smoking are Heart Disease and Lung Cancer.
<span>The correct answer is true; insufficient flexibility does indeed increase an athlete's risk of an injury. This is because a less flexible muscle is more likely to be pulled or torn by movement than one that is able to be moved in a greater range of motion. Thus, it is important for athletes to work of their flexibility.</span>
<span>They benefit from having the respiratory </span>system<span> give oxygen and take away carbon dioxide. Muscle </span>cells benefit<span> by having circulatory </span>system<span> bring them blood and oxygen. The heart pumps blood towards the arteries, arteries carry blood to the </span>cells<span>.</span>
