tetrad defined in 1951 yeartetrad - tetrad;
tetrad - (1) (Bot.). Group of four spores formed by meiosis within a spore mother-cell, e.g. formation of microspores within a micro-spore mother-cell. The process is often described as tetrad division. (2) Paired chromosomes of meiosis, after each chromosome has become visibly two-stranded.
near tetrad in Knolik
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