Question

how is euchromatin different from heterochromatin? both consist of the 10-nm fiber, which during interphase is more densely arranged in euchromatin, and more loosely arranged in heterochromatin. heterochromatin is the more densely arranged chromatin that is found during mitosis and meiosis, while euchromatin is the more loosely arranged chromatin found throughout the nucleus in interphase. both consist of the 10-nm fiber, which during interphase is more densely arranged in heterochromatin, and more loosely arranged in euchromatin. heterochromatin is accessible to the enzymes responsible for transcribing genes, while euchromatin is not.

Answer 1

Euchromatin is less densely packed, active in transcription, and found in interphase, while heterochromatin is tightly packed, contains inactive genes, and is characteristic of cell division phases.

Step-by-step explanation:

• The key difference between euchromatin and heterochromatin is that euchromatin is less densely packed, allowing genes to be active in transcription, while heterochromatin is much more tightly packed and usually contains genes that are not expressed. During interphase, euchromatin has DNA packaged around nucleosomes in a "beads on a string" structure which is not further compacted, making the DNA accessible to enzymes for transcription. Meanwhile, heterochromatin, found at regions like the centromere and telomeres, is densely packed thereby rendering the DNA inaccessible for gene expression.

Structurally, euchromatin consists of a 10-nm fiber structure resembling a string with beads (nucleosomes), which can further condense into a 30-nm fiber, but remains in a state where transcription factors and RNA polymerases can access the DNA. Conversely, heterochromatin is even more tightly compacted and includes additional proteins that make it transcriptionally inactive. Furthermore, during cell division (mitosis and meiosis), chromatin condenses maximally into chromosomes, and heterochromatin being highly condensed is characteristic of these phases, while euchromatin is typical of interphase.