etAP gene expression 2.4.26

Why are control elements and the transcription factors they bind important in eukaryotic genes?

• They are necessary for DNA replication.

• They are critical to the precise regulation of gene expression in different cell types.

• They help in the direct synthesis of proteins.

• They are involved in the repair of DNA.

What are the segments of noncoding DNA associated with most eukaryotic genes called that serve as binding sites for transcription factors?

• Introns

• Exons

• Control elements

• Replication origins

What is the role of chromatin-modifying enzymes in the regulation of transcription initiation?

• They replicate DNA to ensure there is enough for transcription.

• They provide initial control of gene expression by altering DNA's ability to bind the transcription machinery.

• They bind to RNA polymerase to initiate transcription directly.

• They transport mRNA out of the nucleus.

Can chromatin modifications that do not alter DNA sequence be passed to future generations of cells?

• Yes, but only through maternal lineage

• No, because they do not involve DNA sequence changes

• Yes, they may be passed to future generations of cells

• No, because chromatin modifications are temporary and not heritable

Tags

NGSS.HS-LS3-2

What is epigenetic inheritance?

• The inheritance of traits through direct alterations in the DNA sequence

• The inheritance of traits through mechanisms that do not involve changes to the nucleotide sequence

• The inheritance of physical traits only from the maternal side

• The inheritance of traits determined by environmental factors exclusively

What can DNA methylation cause in terms of gene activity?

• Short-term activation of genes.

• Long-term activation of genes.

• Long-term inactivation of genes.

• Immediate inactivation of genes.

Tags

NGSS.HS-LS3-2

What is the effect of DNA methylation on the transcription of certain DNA bases?

• It increases transcription.

• It has no effect on transcription.

• It reduces transcription.

• It completely stops transcription.

What do almost all the cells in an organism have in common?

• They contain different genomes.

• They contain an identical genome.

• They express the same genes.

• They are involved in transcription.

What role does CRP play in the cell?

• CRP detaches from the lac operon when lactose levels increase

• CRP attaches to the lac operon to increase transcription

• CRP helps regulate operons that encode enzymes used in catabolic pathways

• CRP prevents the cell from using glucose

What is the effect of the addition of methyl groups (methylation) to chromatin?

• It promotes the initiation of transcription

• It opens up the chromatin structure

• It condenses chromatin and reduces transcription

• It attaches acetyl groups to amino acids in histone tails