Question

Punnet square-
The fruit weight of a certain variety of avocado is determined by two gene pairs: AABB produces fruits weighing 2 kg each, and aabb produces fruits weighing 1 kg each. Each allele represented by a capital letter contributes 1/4 kg to the weight of the fruit. When a plant that produces 2 kg fruit is crossed with a plant that produces 1 kg fruit, all the offspring produce fruit weighing 1.5 kg each. What would be the weight of the fruits produced in the F2 plants if two of these f1 plants mate?

Answer 1

here is the answer bye :)

Answer 2

Weight of the fruits in F2 plants are- 2kg, 1.75 kg, 1.5 kg, 1.25 kg, 1 kg

Explanation:

• AABB produces fruit weighing  2kg each, aabb produce fruit with 1 kg. each allele represent $\frac{1}{4}$ kg to the weight.
• so, each A allele contribute 2×$\frac{1}{4}$=$\frac{1}{2}$ kg and each B allele contribute $\frac{1}{2}$kg

• Each a allele contribute 1×$\frac{1}{4}$=$\frac{1}{4}$ kg, each b allele contribute $\frac{1}{4}$kg

         P               AABB × aabb

          F1                     AaBb

       weight of the fruit in F1 is $\frac{1}{2}$+$\frac{1}{4}$+$\frac{1}{2}$+$\frac{1}{4}$=$\frac{3}{2}$=1.5 kg

         F2                 AaBb × AaBb

       

                      AB         Ab         aB           ab

        AB     AABB      AABb     AaBB     AaBb

         Ab     AABb      AAbb     AaBb      Aabb

     

         aB      AaBB      AaBb    aaBB       aaBb

          ab     AaBb         Aabb    aaBb      aabb

      weight of the fruits in F2 are-

     a) AABB= $\frac{1}{2} \f$×4= 2kg

      b) AABb=$\frac{1}{2}$×3+$\frac{1}{4}$=$\frac{7}{4}$=1.75kg

     c) AaBB = $\frac{1}{2}$×3+$\frac{1}{4}$= 1.75kg

      d) AAbb= $\frac{1}{2}$×2+$\frac{1}{4}$×2=1.5kg

      e) AaBb=$\frac{1}{2}$×2+$\frac{1}{4}$×2=1.5kg

      f)  Aabb= $\frac{1}{2}$+$\frac{1}{4}$×3=$\frac{5}{4}$=1.25 kg

      g) aaBB = $\frac{1}{4}$×2+$\frac{1}{2}$×2=$\frac{3}{2}$= 1.5 kg

      h) aaBb = $\frac{1}{4}$×3+$\frac{1}{2}$=$\frac{5}{4}$=1.25 kg

      i) aabb=$\frac{1}{4}$×4= 1 kg