Final answer:
The features of the epigenome include its establishment during early development and its dynamic regulation, making option 3) Both A and B the correct answer. The epigenome contributes to heritable changes in gene expression without DNA sequence alterations and impacts cell differentiation.
Step-by-step explanation:
The features of the epigenome include being established very early in development and being dynamically regulated. This means that the correct answer to the question would be option 3) Both A and B. The epigenome is involved in epigenetic control, which influences changes in gene expression without altering the nucleotide sequence of DNA. These modifications are heritable and can initiate chromatin rearrangements, affecting the expression of genes and playing a crucial role in the differentiation of cells through development.Gene expression is regulated at several levels: epigenetic, transcriptional, post-transcriptional, translational, and post-translational. Epigenetic changes can open or close chromosomal regions, allowing or preventing transcription, and are thus essential for the proper function and identity of cells.