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Biosphere 2 was a tremendous success, Many people don't realize that hundreds of papers were written about it.
According to the evolution theory, the first insects appeared about 400 million years BC in the Devonian Period.
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.