MCQ
Assertion : $DNA$ is associated with proteins.

Reason : $DNA$ binds around histone proteins that form a pool and the entire structure is called a nucleosome.

  • If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
  • B
    If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
  • C
    If the Assertion is correct but Reason is incorrect.
  • D
    If both the Assertion and Reason are incorrect.

Answer

Correct option: A.
If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
a
A chain of $DNA$ has $140$ base pairs, make $1\frac {3}{4}$ turns and twist around a histone octamer forming nucleosome. The core of nucleosome consists of $4$ histones $H_2A,\,H_2B,\,H_3$ and $H_4$.

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