Parental F1 F2 In a monohybrid cross, Mendel examined a single trait, such as flower color.

  1. Plants were allowed to self-fertilize until true-breeding lines were established.

  2. Plants with different traits were cross-fertilized to yield an offspring generation (F1).

  3. The 2nd generation plants were self-fertilized to yield a 2nd offspring generation (F2).