The Chondrichthyes are the cartilaginous fishes including the sharks, rays,<span>skates and chimeras. The Osteichthyes are the bony fish. Both of these groups </span>became established during the Devonian Period about 400 million years ago. The Chondrichthyes <span>differ from the Osteichthyes in many respects, including their</span><span>
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A relatively large molecule that has an electrical charge associated with it, regardless if it is full charge or partial. Would require facilitated diffusion to enter a cell.
Eg - complex sugars, or disaccharides - fructose, or amino acids, ions - Na + or Ca +.
