Heme, a complex heterocyclic compound, is an organic molecule derived from porphyrin with an iron atom at the centre.

血红素(一种复杂的杂环化合物)是来自中心含铁原子的的一种有机分子。

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Thiamine (vitamin B1) Organic compound, part of the vitamin B complex, necessary in carBohydrate metaBolism.

硫胺素(亦称维生素b1)：有机化合物，维生素B复合体的一种，为日常饮食所必需。

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Lignin: Complex oxygen-containing organic compound, a mixture of polymers of poorly known structure.

木质素：一种复杂的含氧有机物，是结构尚不清楚的多种聚合物的混合物。

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One key element in searching for life on Mars is the presence of methane in the Martian atmosphere As a simple carbon compound, methane is often a precursor to the formation of the complex organic chemicals that make life possible.

FORBES: Curiosity Sniffs The Martian Atmosphere But Finds No Sign Of Life