Question

The net electric charge on DNA and histones is:

• A. both positive
• B. both negative
• C. negative and positive, respectively
• D. zero

Answer 1

The correct option is C negative and positive, respectively

Charge on DNA:

DNA is the polymer of nucleotides which contains pentose sugar, nitrogenous base and phosphate groups. These phosphate groups carry the negative charge due to the physiological pH of the cell. Thus, DNA is negatively charged.



Histones:

Histones are positively charged proteins because of the abundance of basic amino acids such as lysine and arginine. DNA wraps around positively charged histone proteins for its packaging.




Final answer: c. negative and positive, respectively