Please solve 51. What Alternate groves of DNA is being asked about?

Dear student,
Please find below the answer:

The correct option is (a).

A DNA segment has two grooves- one major and one minor.

• When the backbones of the DNA helix are far apart, it is called a major groove.
• When the backbones of the helix are close to each other, it is called a minor groove.

The function of major and minor grooves is to align the DNA such that it gets a helical shape. These grooves help to regulate DNA replication and transcription. These provide binding sites for transcription factors or DNA binding proteins during transcription and replication.

Hope this clears your doubt.
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