External Respiration takes place in the Trachea. When oxygen and co2 "switch" its where they connect and making this external respiration!
I hope this helps you!
At the bottom of the pyramid is the grass where as you move up the number is less
<span>As humans change the way we live on the planet, the way that nitrogen moves around the Earth also changes. Nitrogen atoms may seem small enough to be easily overlooked. We look right through the ones in the air, do we not? Yet recent changes in the nitrogen cycle are causing a very noticeable effect on natural environments and human health. Lakes are clogged with aquatic weeds. Dead zones have formed in areas of the oceans where animals can not survive. Air pollutants that contain nitrogen are decreasing air quality and greenhouse gases that contain nitrogen are becoming more common.</span>
Monday 2pm, since it was forecasted to make landfall at that time