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simple chemical substances needed by the body in relatively small amounts for normal growth and development. They usually occur in the form of ions.
plastids responsible for pigment synthesis and storage. They mainly contain carotenoids, but can...
a substance, usually a liquid, in which other substances can dissolve.
simple epithelium with elongated, cells that lines the stomach, small intestine, urethra, vas...
those species that are found only in a particular area or region and nowhere else on Earth.