Frederick griffith performed an experiment in which a live culture of avirulent "rough" strain streptococcus pneumoniae bacteria were mixed with dead cells of virulent "smooth" streptococcus pneumoniae bacteria. subsequently, the "rough" bacteria were "transformed" into "smooth" bacteria capable of killing mice. this experiment demonstrated that

In a classic experiment using pea shape, mendel conducted two separate genetic crosses. in the first cross the parent plants were “true breeding” for pea shape; one had round peas ( r )and the other had wrinkled (r). the first cross produced a filial 1 generation of all round peas. in the second cross, mendel bred plants from the filial 1 generation. this cross produced different results. out of approximately 1000 plants, about 75% were round and 25% were wrinkled.