Food poisoning is caused by bacteria and, sometimes, viruses or other germs. They can get into the food we eat or the liquids we drink. We can't taste, smell, or see these germs (at least not without a microscope). But even though they're tiny, they can have a powerful effect on the body.
A woman is jogging on a wooded trail. Photo Credit Stockbyte/Stockbyte/Getty Images. Consisting of a series of body parts including the lungs, diaphragm and nasal cavity, the respiratory system is responsible for transporting oxygen and carbon dioxide to and from muscles and tissues.During exercise, the respiratory system increases to meet the demands of the working muscles.o meet the increasing oxygen demands from the working muscles, additional oxygen must be transported through the blood vessels. During exercise, the sympathetic nerve stimulates the veins to constrict to return more blood to the heart.
When Not Exercising. Inhalation and exhalation is the result of the change of volume in the thorax. When you inhale, the diaphragm and external intercostals contract and lower the thorax, expanding the lungs. This causes the pressure inside the lungs to decrease, facilitating the flow of air into the lungs.