Eduprobe
Question:
During a monohybrid cross involving a tall pea plant with a dwarf pea plant, the offspring populations were tall and dwarf in equal ratio. Work out a cross to show how it is possible.
Solution:
To have tall and dwarf progeny in equal ratio, both parents should have atleast one copy of recessive allele (t). This makes tall plant being a heterozygous dominant (Tt). Being recessive character, dwarfism can be expressed only by homozygous genotype; genotype of dwarf parent is "tt".
Parents : Tt x tt
Tt x tt
| T | t | |
|---|---|---|
| T | TT | Tt |
| t | Tt | tt |
Phenotypic ratio= 1 tall : 1 dwarf.