Question

Fruit shape in shephered purse (Capsella bursa) is of two types-triangular and top-shaped. Triangular fruit shape (T) is dominant over top-shape (t). Following table summarises the results of several crosses.
CrossResultStrain 1ÃttAll triangularStrain 2Ãtt1 triangular : 1 top-shapedstrain 3ÃttAll top-shapedStrain 4ÃTt3 triangular : 1 top-shaped
Which pair of strains possess the genotyoe Tt ?

Answer 1

Answer:

Explanation:

The strain 2 that has one triangular and one top shaped fruit will have the genotype 'Tt' which is heterozygous and results hence with a cross recessive genotype 'tt' two genotype the 'Tt' and 'tt' that will give the triangular and top-shaped fruit respectively. The strain 4 also has heterozygous 'Tt' genotype and will give with the cross of 'tt' 3 heterozygous and one recessive genotype and hence 3 triangular and 1 top shaped fruit.  

So, the correct answer is ' Strains 2 and 4'.