Question

A plant breeder crosses a pure-breeding tall pea plant with a pure-breeding dwarf pea plant and observes that all the F1 offspring are tall, with no intermediate height plants appearing. When these F1 tall plants are then self-pollinated, the breeder finds that the F2 generation contains both tall and dwarf plants in an approximate ratio of 3:1. Which two of Mendel's principles are together demonstrated by this complete two-generation experiment?

Q: Answer-A plant breeder crosses a pure-breeding tall pea plant with a pure-breeding dwarf pea plant and obse...

The complete disappearance of the dwarf trait in F1 all tall demonstrates Mendels principle of dominance, while its reappearance in the F2 generation in an approximate 31 ratio demonstrates the principle of segregation, showing that the recessive allele for dwarfism was present but masked in the heterozygous F1 plants and separated out again during gamete formation.