Question

Which of the given is not a test cross?​

Answer 1

answer is :-

2

Explanation:

hope this is correct

plz follow me

mark me as brillant

Answer 2

Answer:

OPTION (4) Red-flowered 4 o'clock plant $\times$ White-flowered 4 o'clock plant

Explanation:

Test cross is a cross between a recessive parent plant and a progeny whose genotype is to be known. The phenotype of this progeny is the dominant trait but the genotype is unknown.

Here, we have to identify which of the following pair is not a test cross.

1. Tall pea plant $\times$ Dwarf pea plant: Here, dwarf pea plant is a recessive trait and tall pea plant is the phenotype, since we do not know the genotype, this qualifies as a  test cross.
2. Yellow pod pea plants $\times$ Green pod pea plants: In pod color, green is the dominant trait and yellow is recessive. Here, the phenotype is dominant but the genotype is unknown. Therefore, this is a test cross.
3. Brown body Drosophila $\times$ Yellow body Drosophila: Here, brown color is dominant whereas yellow is recessive. This is a test cross.
4. Red flowered 4 o'clock plant $\times$  White-flowered 4 o'clock plant: This cannot be a test cross because the progeny, in this case, will have pink color because the 4 o'clock plant shows incomplete dominance. The progeny will neither show red color nor white. It will be pink.

Hence, the cross between the red-flowered 4 o'clock plant and the white-flowered 4 o'clock plant is not a test cross.