Karl and Hally Sax crossed Aegilops cylindrica (2n = 28), a wild grass found in the Mediterranean region, with Triticum vulgare (2n = 42), a type of wheat (K. Sax and H. J. Sax. 1924. Genetics 9:454-464). The resulting F, plants %3D from this cross had 35 chromosomes. Examination of metaphase I in the F, plants revealed the presence of 7 pairs of chromosomes (bivalents) and 21 unpaired chromosomes (univalents). a. If the unpaired chromosomes segregate randomly, what possible chromosome numbers will appear in the gametes of the F, plants? b. What does the appearance of the bivalents in the F, hybrids suggest about the origin of Triticum vulgare wheat?