Dominant and recessive traits Original Scenario-Based Practice

Questions

1. 1.

   In an arboretum of mythical flora, botanists cultivate lunar lilies where a dominant allele ($L$) produces luminous silver petals, while a recessive allele ($l$) results in matte obsidian petals. Crossing a true-breeding silver plant ($LL$) with an obsidian plant ($ll$) yields an entirely silver-petaled $F_1$ generation. If two of these $F_1$ plants are crossed to produce an $F_2$ generation, which prediction correctly describes the phenotypic reappearance of the recessive trait?

   • A) All $F_2$ offspring will have intermediate gray petals because recessive traits blend irreversibly into dominant backgrounds.
   • B) Approximately 50% of the $F_2$ offspring will display obsidian petals because the recessive allele mutates the dominant allele during gamete formation.
   • C) Approximately 25% of the $F_2$ offspring will display obsidian petals because the recessive allele remains unchanged and is expressed in the homozygous $ll$ state.
   • D) Approximately 75% of the $F_2$ offspring will display obsidian petals because recessive traits become dominant after skipping a generation.

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