When guard cells lose potassium ions, water diffuses out of the cells by osmosis. As water leaves the cells, they become flaccid and less bowed, which closes the stomata between them.
The
Blood<span> moves in the heart through two large veins, the
inferior and superior vena cava, and exhausting oxygen-poor blood from the body into the right atrium. The pulmonary vein discharges oxygen-rich blood, from the lungs into the left atrium.</span>
