Question

Read the following statements and select the correct option.
(i) Loosely packed and lightly stained region of chromatin are called as heterochromatin.
(ii) Densely packed and dark stained region of chromatin are called as euchromatin.
(iii) A typical nudeosome contains $200$ bp of $DNA$ helix

• A. Statements (i) and (ii) are true, but statement (iii) is false
• B. Statements (i) and (ii) are false, but statement (iii) true
• C. Statements (ii) and (iii) are true, but statement (iv) false
• D. All the statements are true

Answer 1

Answer: (B)

A typical nudeosome contains $200bp$ of $DNA$ helix. Nudeosomes constitute the repeating unit of a structure in nucleus called chromatin. Chromatin is held over a scaffold of non-histone chromosomal (or $NHC$) proteins. At some places chromatin is densely packed to form darkly stainined heterochromatin. At other places chromatin is loosely packed. It is called euchromatin. It is transcriptionally active chromatin whereas heterochromatin is transcriptionally inactive and late replicating or heteropycnotic.