Forex Market Trading Hours. T he ability of the Forex to trade over a 24-hour period is due in part to different time zones and the fact it is comprised of a network of computers, rather than any one physical exchange that closes at a particular time.
The diaphragm also contracts to extend the cavity further downwards. Due to the function of the pleural membrane, the size of the lungs is increased which, in turn, creates an area of lower air pressure inside the lungs; hence, air is drawn into the lungs. Exhalation is the process of expelling air out of the lungs.
Excretion. Excretion is the process by which waste products of metabolism and other non-useful materials are eliminated from an organism. In vertebrates this is primarily carried out by the lungs, kidneys and skin. This is in contrast with secretion, where the substance may have specific tasks after leaving the cell.