Concept explainers
SCIENTIFIC INQUIRY
DRAW IT In this chapter, you read that bread wheat (Triticum aestivum) is an allohexaploid, containing two sets of chromosomes from each of three different parent species. Genetic analysis suggests that the three species pictured following this question each contributed chromosome sets to T. aestivum. (The capital letters here represent sets of chromosomes rather than individual genes.) Evidence also indicates that the first polyploidy event was a spontaneous hybridization of the early cultivated wheat species T. monococcum and a wild Triticum grass species. Based on this information, draw a diagram of one possible chain of events that could have produced the allohexaploid T. aestivum.
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