Question

Regulation of Gene Expression in Eukaryotes Part A -Modification of chromatin structure Which statements about the modification of chromatin structure in eukaryotes are true? Select all that apply. View Available Hint(s) Acetylation of histone tails is a reversible process Some forms of chromatin modification can be passed on to future generations of cells. DNA is not transcribed when chromatin is packaged tightly in a condensed form. O Acetylation of histone tails in chromatin allows access to DNA for transcription. Deacetylation of histone tails in chromatin loosens the association between nucleosomes and DNA Methylation of histone tails in chromatin can promote condensation of the chromatin Submit Part B Regulation of transcription initiation toh f D includes the fantasin gene, along with it

Answer 1

Answer A: - The following statements are correct:

- Some forms of chromatin modification can be passed on to future generations of cells.

(Changes in chromatin can be passed on to future generations through epigenetic inheritance. There are several studies regarding this)

- Acetylation of histone tails is a reversible process.

- Acetylation of histone tails in chromatin allows access to DNA for transcription.

(Acetylation of histone tails reduces the attraction between neighboring nucleosomes, causing chromatin to assume a looser structure and allowing access to the DNA for transcription. If the histone tails undergo deacetylation, chromatin can recondense, once again making DNA inaccessible for transcription.)

- DNA is not transcribed when chromatin is packaged tightly in a condensed form.

(When chromatin is condensed, DNA is not accessible for transcription.)

- Methylation of histone tails in chromatin can promote condensation of the chromatin.

(Methylation of histone tails can promote either the condensation or the decondensation of chromatin, depending on where the methyl groups are located on the histones.)

Answer B: - The following statements are true:

-Control elements C, D, and E are distal control elements for the imaginin gene.

-Both the fantasin gene and the imaginin gene will be transcribed at high levels when activators specific for control elements A, B, C, D, and E are present in the cell.

-The fantasin gene will be transcribed at a high level when activators specific for control elements A, B, and C are present in the cell.