One of the most striking paradoxes of Internet culture is that children are the most computer literate among us, but their vulnerability to online predators prevents their being able to enjoy or explore freely what is likely to be the defining medium of their lives.
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Like other growth media, the formulations of agar used in plates may be classified as either " defined " or " undefined "; a defined medium is synthesized from individual chemicals required by the organism so the exact molecular composition is known, whereas an undefined medium is made from natural products such as yeast extract, where the precise composition is unknown.
