334

You visited us 334 times! Enjoying our articles? Unlock Full Access!

Byju's Answer

Standard XII

Biology

Definition and Significance of Test Cross

When the two ...

Question

When the two parental genotypes BB and bb are crossed, the genotype of all F $_{1}$ plants is Bb. On selfing of F $_{1}$ generation, how many dominant phenotypes will be produced in F $_{2}$ generation?

No worries! We‘ve got your back. Try BYJU‘S free classes today!

25%

No worries! We‘ve got your back. Try BYJU‘S free classes today!

50%

No worries! We‘ve got your back. Try BYJU‘S free classes today!

75%

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

100%

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is E 75%
When the parents BB and bb are crossed, the gametes formed are B, B and b, b respectively. The genotype of all the offsprings in F $_{1}$ generation is Bb. When Bb is selfed, the gametes will be B and b for both the parents. The progeny produced will be BB, Bb, Bb, and bb. There are 3 dominant phenotypes observed out of total 4 offspring. So, the percentage of dominant phenotypes in F $_{2}$ generation will be 75%.
Thus, the correct answer is option '75%'.

Suggest Corrections

Similar questions

Q. In the dihybrid cross, the two parental genotypes are AABB and aabb. The genotype of all F

_{1}

plants is AaBb. What phenotype ratio will be observed in the F

_{2}

generation?

List I	List II
A. $B B \times b b$	1. 100% bb
B. $B b \times B b$	2. 25% BB, 50% Bb, 25% bb
C. $B B \times B B$	3. 100% BB
D. $b b \times b b$	4. 100% Bb

Match the genetic cross of the parents on the left with the genotypes on the right of the offspring most likely to be produced from that cross.

Q. The following crosses were performed between parental lines with indicated genotypes.
(i)

B B \times B b

(ii)

A A b b \times a a B B

(iii)

B B \times b b

(iv)

B b \times B b

(v)

A A \times A A

(vi)

b b \times B b

The above crosses that are expected to produce only

50

% homozygotes among the F

_{1}

progeny are

A blue colour flower plant denoted by BB is crossbred with that of white colour flower plant denoted by bb.

(a) State the colour of flower you would expect in their $F_{1}$ generation plants.

(b) What must be the percentage of white flower plants in $F_{2}$ generation if flowers of $F_{1}$ plants are self-pollinated?

A tall violet flowered plant (TTVV) is crossed with a dwarf white flowered plant (ttvv). When the $F_{1}$ plants are self-pollinated, a total of 1600 $F_{2}$ plants are produced. How many plants of $F_{2}$ generation are similar to the original parents in terms of both genotype and phenotype?

Join BYJU'S Learning Program

When the two parental genotypes BB and bb are crossed, the genotype of all F1 plants is Bb. On selfing of F1 generation, how many dominant phenotypes will be produced in F2 generation?

When the two parental genotypes BB and bb are crossed, the genotype of all F $_{1}$ plants is Bb. On selfing of F $_{1}$ generation, how many dominant phenotypes will be produced in F $_{2}$ generation?