1 lactase intolerance, and. 2  malabsorption of certain foods. 3  Much of the gas generated is due to microbial breakdown of foods so that gases, for example, hydrogen, carbon dioxide, and methane are generated; the odor is from other trace waste gases or compounds such as skatole and sulfur-containing substances.
Best Answer: Blood enters the heart through the right atrium, it then goes into the right ventricle to be pumped via the pulmonary artery to the lungs to be re-oxygenated. After that it heads, via the pulmonary vein, to the left atrium in the heart to be pumped around the rest of the body again via the aorta.
As your heart contracts, it forces the oxygenated blood through another one-way valve into your aorta, which is the largest artery in your body and the first artery in your systemic circuit. When deoxygenated blood returns from the systemic circuit, it enters your heart's right atrium, flows through a one-way valve into the right ventricle, and gets pushed through another one-way valve to reenter the pulmonary circuit and head for your lungs.