Commonly called breathing which is air moved into and out of the lungs. During inspiration and expiration so the gases there are continually changed and refreshed. External respiration. Oxygen diffuses from the lungs to the blood and carbon dioxide diffuses from the blood to the lungs. exchange between external environment (alveoli) & blood*. Transport of respiratory gases. oxygen is transported from the lungs to the tissue cells to the lungs. **THE cardiovascular system accomplishes this transport using blood as the transporting fluid. Internal respiration. oxygen diffuses from the blood to tissue cells, and carbon dioxide diffuses from tissue cells to blood.
While strong stimulants (such as cocaine) can cause seizures, the milder stimulant effects of nicotine and caffeine don't seem to impact on seizure frequency (except with extreme excess use).
The short answer is NICOTINE--the chemical that causes you to become addicted to cigarettes. Nicotine affects your brain, changes your mood, and causes you to want more and more. When you smoke, your body immediately responds to the nicotine, but this high only lasts about 10 seconds!!Because it is so addictive, nicotine also causes unpleasant withdrawal side effects when you try to quit.HOWEVER, most of these symptoms will not last long and they should all be gone within a few weeks.hen you smoke, your body immediately responds to the nicotine, but this high only lasts about 10 seconds!! Because it is so addictive, nicotine also causes unpleasant withdrawal side effects when you try to quit.