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Which of the following statements about epigenetic inheritan…

Which of the following statements about epigenetic inheritance are true? Select true or false for each statement. It is possible for epigenetic marks to be heritable from parent to offspring. [blank1] “Imprinting” is a phenomenon where some alleles become permanently imprinted in a lineage, regardless of whether the allele came form a male or female gamete. [blank2] Some chromosomes get nearly completely silenced by epigenetic modifications; those modifications are inherited through mitosis but not meiosis. [blank3] Histone modifications like methylation and acetylation can be inherited through mitosis. [blank4]

In prokaryotes, the trp operon is finely regulated to ensure…

In prokaryotes, the trp operon is finely regulated to ensure that there is a steady supply of tryptophan. One mechanism through which this operon is regulated is the formation of stem loops on the mRNA transcript. The diagram below illustrates how these hairpins form in high (top) or low (bottom) tryptophan conditions. Now imagine that an in-frame deletion mutation occurs in region 3, preventing its stem loop formation with only region 4 (light blue), but does not prevent stem loop formation with region 2 (red). This effectively makes the formation of the terminator hairpin impossible, but has no other effect on the operon (i.e. the affected amino acid sequence of the “leader” trpL has no effect). Of the following scenarios, which is the most reasonable outcome of this mutation?