Fig. 3. The mek1 mutant is defective in spore viability and meiotic recombination. (A) Distribution of tetrad types. The percentages of tetrads with 4, 3, 2, 1 and 0 viable spores (4-sv, 3-sv, 2-sv, 1-sv and 0-sv, respectively) are represented. Tetrads were dissected from crosses between wild-type (S778xS781) and mek1 strains (S1291xS1292) after 2 days on MEA plates. (B) The frequency of intergenic meiotic recombination was measured on the leu1-his5 interval on chromosome II by random spore analysis of crosses between wildtype (PN22 x S1285) and mek1 (S1300xS1301) strains.