Question

Heterochromatin is

• A. Darkly stained part of chromatin.
• B. Lightly stained part of cristae.
• C. Lightly stained part of grana.
• D. Scattered lobes in cytoplasm.

Answer 1

The correct option is A Darkly stained part of chromatin.

Heterochromatin is the darkly stained part of chromatin. The heterochromatin is condensed in the secondary constrlction I and II of the chromosome. Heterochromatin is a tightly packed form of DNA, which comes in different varieties. These varieties lie on a continuum between the two extremes of constitutive and facultative heterochromatin. Both play a role in the expression of genes. Chromatin is found in two varieties: euchromatin and heterochromatin. Heterochromatin has been associated with several functions, from gene regulation to the protection of the integrity of chromosomes; some of these roles can be attributed to the dense packing of DNA, which makes it less accessible to protein factors that usually bind DNA or its associated factors.