Question

Read the assertion and reason carefully to mark the correct option in question.

Assertion: Interphase nucleus has a loose and distinct network of fibre called chromatin.

Reason: Chromatin contains $RNA,DNA$ and histone proteins but non-histone proteins are absent.

• A. If both assertion and reason are true but the reason is not the correct explanation of the assertion.
• B. If both assertion and reason are false.
• C. If assertion is true but the reason is false.
• D. If both assertion and reason are true and the reason is the correct explanation of the assertion.

Answer 1

The correct option is B If both assertion and reason are false.

Assertion

Interphase nucleus has a loose and distinct network of fibre called chromatin.

Elaboration:

The $G_1,S$, and $G_2$ phases are included in the interphase of the cell cycle. During this phase the cell prepares itself, replicates its $DNA$, and gets ready for mitosis. Genetic material is present in the form of beads-on-string structure inside the nucleus of the cell. This structure is known as chromatin. They form a loose and indistinct structure.

Reason

Chromatin contains $RNA,DNA$ and histone proteins but non-histone proteins are absent.

Elaboration:

Chromatin is a network of nucleoprotein fibres present inside the nucleus. It consists of $DNA$, protein and $RNA$.

The chromatin organisation involves compact packaging of $DNA$ with the help of histone proteins. Additionally, non-histone proteins are present which have a key role in organisation and regulatory functions.

Final answer

(D) If both assertion and reason are false.