Genetics Ch. 19 Gene Regulation in Eukaryotes

1. Transcription in prokaryotes and eukaryotes is similar in that

E. both are regulated by attachment of proteins to DNA adjacent to the gene being transcribed.

2. The primary point of control for most genes for the amount of gene product synthesized is

C. initiation of transcription.

3. Zinc-finger peptide motifs are responsible for what aspect of protein function?

B. DNA binding

4. DNA sequences that serve as binding sites for proteins regulating transcription and are often found adjacent to a gene are said to be

B. cis-acting.

5. What is the name of the cis-acting DNA sequence that serves as the binding site for the transcriptional initiation complex?

A. Promoter

6. What is the term for the cis-acting DNA sequences that often function at a distance from the gene they are regulating?

A. Enhancer element

7. In generating a reporter construct to study gene regulation, the reporter gene introduced replaces

D. the coding region of the gene being studied.

8. Trans-acting proteins that influence transcription are commonly referred to as

D. transcription factors.

9. What does RNA polymerase I synthesize?

E. rRNA

10. Which of the following is NOT true of enhancer DNA sequences?

A. They contain the TATA box regulatory element.

11. A transcription factor that increases initiation of transcription by associating with an enhancer element is termed a(n)

B. activator.

12. What is the name for the basal transcription factors that associate with TBP to assist in initiating transcription from eukaryotic class II genes?

C. TAFs

Breifly describe how transcription factors regulate gene expression in Eukaryotes

Transcription factors regulate gene expression in eukaryotes by binding to DNA at promoters or enhancers to activate or repress transcription.

Why TRP operon is a repressible regulation and anaboli pathway?

The trp operon is repressible because it’s normally on and only turned off when tryptophan is present (the product acts as a corepressor). It’s part of an anabolic pathway because it builds tryptophan, an essential amino acid.

Why the Lac operon is an inducible gene regulation in catabolic pathway?

The lac operon is inducible because it’s normally off and turned on only when lactose is present (the inducer removes the repressor). It’s part of a catabolic pathway because it breaks down lactose for energy.