Answer:
q1 : ribosomes because they are responsible for protein synthesis
q2 : by transporting potassium ions into the cell and sodium ions out of the cell maintaining a concentration gradient
q3 : seawater contains a high concentration of sodium and chlorine ions that the Atlantic cod gets rid of by actively transporting them out of its body
Passive transport<span> is a movement of </span>biochemicals<span> and other </span>atomic<span> or </span>molecular<span> substances across </span>cell membranes through <span>concentration gradients</span><span> without need of </span>energy<span> input. Unlike </span>active transport<span>, it does not require an input of cellular energy because it is instead driven by the tendency of the system to grow in </span>entropy<span>. The rate of passive transport depends on the </span>permeability<span> of the cell membrane, which, in turn, depends on the organization and characteristics of the membrane </span>lipids<span> and </span>proteins<span>. The four main kinds of passive transport are simple </span>diffusion<span>, </span>facilitated diffusion<span>, </span>filtration<span>, and </span>osmosis.