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.
Blood returns to the heart from the lungs via the pulmonary veins. The blood goes into the left atrium. When the left atrium contracts, blood travels through a valve into the left ventricle.The left ventricle is a very important chamber because it pumps blood through a valve and into the aorta. The aorta-the main artery of the body-receives all the blood that the heart pumps out and sends it to the rest of the body.lood returns to the heart from the lungs via the pulmonary veins. The blood goes into the left atrium. When the left atrium contracts, blood travels through a valve into the left ventricle.