Trace element
A trace element was an element needed by a lifeform to maintain a proper physiology.

According to a diagnostic analysis ran by Doctor Beverly Crusher in 2364, excess or deficiency of trace elements could have a negative impact on chromosomes. ()

When the Krenim weapon ship erased the Garenor homeworld from history, Annorax asked for the trace elements. Obrist reported they were diminishing. ()

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Physiology