Answer:
Acetylation of histone tails is a reversible process.
DNA is not transcribed when chromatin is packaged tightly in a condensed form.
Methylation of histone tails in chromatin can promote condensation of chromatin.
Acetylation of histone tails in chromatin allows access to DNA for transcription.
Eukaryotic chromatin structure is a highly complex assembly which needs to be simplified in order to undergo process of transcription. Eukaryotic chromatin structure is highly condensed in nature and DNA cannot be access for transcription. Actylation of histone tails is a process in which breaks the bond of attraction between adjacent nucleosomes. It results in chromatin being condensed attains a loose form. Transcription of DNA can occur in a loose chromatin. Methylation can promote condensation or decondensation of chromatin structure depending upon the methyl group present in the histone.
Cells are the most simple level of organization, as tissues contain cells, organs contain tissues and systems contain organs, so R would be your answer.
Answer:
They are transformed by the armies of the United States and China wants to defeat them