Most of the marine animals have a stream lined body, which means, they have a sharp and pointed at the front. The pointed front of the organism allow to cut the resistance of the water. In case, the body is not pointed at the front and it is blunt, the water current and flow would resist the movement of the organism further. So, for the locomotion purpose, it is important to have a streamlined body. Further smooth and hair less body also decrease the resistance during the movement in the water.
<span>One process wherein diffusion is important is the concentration of salt within a cell. When the salt levels are too high within the cell, salt molecules are moving via diffusion to a region of lower concentration. Another process is the movement of carbon dioxide in plant cells, where CO2 moves from regions of high concentration to regions of low concentration.</span>