Question

If the distance between two consecutive base pairs is 0.34 nm and the total number of base pairs of a DNA double helix in a E.coli cell is $4.6\times {10}^6$ bp, then the length of the DNA is approximately

• A. 2.2 mm
• B. 1.13 mm
• C. 1.56 mm
• D. 2.5 mm

Answer 1

The correct option is C 1.56 mm

Length of DNA = Distance between two bp $\times$ number of bp
$=0.34$ nm $\times 4.6\times {10}^6$
$=0.34\times {10}^{–9}\times 4.6\times {10}^6$
$=1.56$mm
$=1.56\times {10}^{–3}$m