Question

How many nucleosomes are present in DNA of a human cell?

• A. $6.6\times 10^9$
• B. $3.3\times 10^9$
• C. $6.6\times 10^7$
• D. $3.3\times 10^7$

Answer 1

Answer: (D)

In a human cell, the length of DNA molecule is about $2.2meter$ , in which about $6.6\times 10^9$ base pairs are present. This DNA is present along with histone protein in the form of 'Beads on string', which is called as a nucleosome. Each nucleosome carries 200 base pairs. So number of nucleosomes $=6.6\times 10^9/200=3.3\times 10^7$ .