I GOT IT nevermind thanks i would really appreciate some help on this, swamped with studies and my brain won't wrap around the mendelian gene crossings here's one: Base height of a plant is 10 cm. Four genes contribute to the height, and each dominant allele contributes 3 cm to height. If you cross a 10-cm plant (quadruply homozygous recessive) with a 34-cm plant, how many phenotypic classes will there be in the F2? so i subtracted 10 from 34 =24. Dividing by 3 I get 8- so does that mean 8 dominant alleles present in one of the parents? don't really know where to go from there.. and another: In guinea pigs the brown coat color allele (B) is dominant over red (b), and the solid color allele (S) is dominant over spotted (s). The F1 offspring of a cross between true-breeding brown, solid-colored guinea pigs and red, spotted pigs are crossed. What proportion of their offspring (F2) would be expected to be red and solid colored? -so is one of the F1 BBSS? And the other bbss? So I don't understand how I can get a red?