Which among the following is said to be transcriptionally active chromatin ?

Euchromatin .

The correct answer is Option (2) -Euchromatin .

Euchromatin is considered transcriptionally active chromatin. Euchromatin and heterochromatin are two types of chromatin found in the nucleus of eukaryotic cells, and they have distinct structural and functional characteristics.

Euchromatin:

• Staining: It stains less intensely and appears lighter under a microscope.
• Function: Euchromatin is transcriptionally active, meaning that it is involved in gene expression.
• Structural Characteristics: Euchromatin has a less condensed and more extended structure.

Heterochromatin:

• Structural Characteristics: Heterochromatin is highly condensed and appears as dark-staining regions under a microscope.
• Function: Heterochromatin is transcriptionally inactive or less active. It is often associated with regions of the genome that are not actively transcribed.
• Staining: It stains more intensely and appears darker under a microscope.

During transcription, the information encoded in DNA is used to synthesize RNA. This process occurs in the euchromatic regions of the genome where the chromatin is less condensed, allowing the necessary molecular machinery to access and transcribe genes.