Cross of true breeding dominant and recessive tomato plants will have:
Phenotype ratio in F1 generation is 4:0
genotype ratio in F1 generation is 4:0.
Step-by-step explanation:
Data given:
Tall vine = dominant TT
dwarf vine = recessive tt
red fruit dominant RR
yellow fruit recessive rr
true breeding tall tomato plant bearing red fruit is TTRR
true breeding dwarf tomato plant bearing yellow fruit = ttrr
the cross is shown in punnet square:
TR TR
tr TtRr TtRr
tr TtRr TtRr
the phenotype ratio- 4:0
the genotype ratio - 4:0
The phenotype is tall vine with red fruit
Genotype is all the progeny are heterozygous dominant.