Question

Find the number of phosphodiester bonds and glycosidic linkages associated with E.coli DNA respectively
Only one correct answer
A. 9.2 × 106-2, 9.2 × 106 - 2
B. 4.6 x 1062, 4.6 × 106 - 2
C. 4.6 x 106, 4.6 x 106
D. 9.2 x 106, 9.2 x 106​

Answer 1

Explanation:

A will be correct Answer,Plz If wrong Then Suggest .e Right one

Answer 2

The number of phosphodiester bonds and glycosidic linkages associated with E.coli DNA respectively is 9.2 × 10⁶ - 2 and 9.2 × 10⁶. In this question option D is correct but option D must be written as  9.2 × 10⁶ - 2, 9.2 × 10⁶

Explanation:

In a double helix, the distance between two consecutive pairs is 0.34 × 10⁻⁹ and the total length of DNA is equal to the distance between two consecutive pairs x the number of base pairs. Let's take N as the number of base pairs.  

Let us consider the  length of the Ecoli DNA is 1.57mm

1.57mm = 0.34×10⁻⁹  × N

         N = 1.57mm ÷ 0.34 × 10⁻⁹  

         N = 4.6 × 10⁶ base pairs

Formula to find number of phosphodiester bonds is 2n-2, Here n is number of base pairs.

2n-2 = 2×4.6 × 10⁶ - 2

        = 9.2 × 10⁶ - 2

Formula to find  number  of glycosidic linkages is 2 × number of base pairs

So, here the  number of base pairs is 4.6 × 10⁶

2 × number of base pairs = 2 × 4.6 × 10⁶

                                          = 9.2 × 10⁶

• Number of phosphodiester bonds in E.coli is 9.2 × 10⁶ - 2
• Number of glycosidic linkages in E.coli is 9.2 × 10⁶