[Lec 5] Mastering Biology: Transcription I Flashcards
State whether the following statement is true or false. The sequence of the -35 element is mostly 5′-TTGACA-3′.
a. True
b. False
a.
What is the process called that converts the genetic information stored in DNA to an RNA copy?
a. Translation
b. Replication
c. Transcription
d. Translocation
c.
DNA does not store the information to synthesize which of the following?
a. DNA
b. Messenger RNA
c. Organelles
d. Proteins
c.
Transcription begins at a promoter. What is a promoter?
a. A nontranscribed sequence on the DNA
b. Part of the RNA molecule itself
c. A site where many different proteins will bind
d. A site found on the RNA polymerase
e. A site in DNA that recruits the RNA Polymerase
e.
Which of the following statements best describes the promoter of a protein-coding gene?
a. The promoter is a nontranscribed region of a gene.
b. The promoter is part of the RNA molecule itself.
c. The promoter is a site at which only RNA polymerase will bind.
d. The promoter is a site found on RNA polymerase.
a.
What determines which base is to be added to an RNA strand during transcription?
a. Base pairing between the two DNA strands
b. The order of the chemical groups in the backbone of the RNA molecule
c. The previous base
d. Base pairing between the DNA template strand and the RNA nucleotides
d.
Which of the following terms best describes the relationship between the newly synthesized RNA molecule and the DNA template strand?
a. Permanently base-paired
b. Complementary
c. Covalently bound
d. Identical
b.
What happens to RNA polymerase II after it has completed transcription of a gene?
a. It begins transcribing the next gene on the chromosome.
b. It joins with another RNA polymerase to carry out transcription.
c. It is free to bind to another promoter and begin transcription.
d. It is degraded.
c.
Explain why regulation of transcription frequently involves the promoter and protein interactions with the promoter.
a. Promotor inhibits transcription through the binding with the DNA polymerase.
b. The RNA polymerase initially binds the promoter sequence, the promoter-RNA polymerase complex initiates transcription.
c. Promotor inhibits the DNA polymerase binding to DNA.
d. The RNA polymerase binds the promoter sequence, the promoter-RNA polymerase complex terminates transcription.
b.
The sigma (σ) subunit binds to the core RNA polymerase enzyme. The function of this sigma factor is to recognize and bind to the promoter of a gene so that transcription can be initiated.
The closeup shows the secondary structure of the sigma (σ) subunit, which consists of four domains. Identify the domains labeled 1-3.
a. C-terminal domain (1), N-terminal domain 1 (2), N-terminal domain 2 (3)
b. C-terminal domain (1), N-terminal domain 2 (2), N-terminal domain 1 (3)
c. N-terminal domain 2 (1), N-terminal domain 1 (2), C-terminal domain (3)
d. N-terminal domain 1 (1), N-terminal domain 2 (2), C-terminal domain (3)
b.
This image shows a space-filling model of the RNA polymerase holoenzyme forThermus thermophilus. Each subunit is a different color. Identify the subunits labeled 1-3.
a. Sigma (σ) subunit N-terminal domain 1 (1), sigma (σ) subunit C-terminal domain (2), beta prime (β‘) subunit (3)
b. Sigma (σ) subunit N-terminal domain 1 (1), sigma (σ) subunit C-terminal domain (2), beta (β) subunit (3)
c. Sigma (σ) subunit C-terminal domain (1), sigma (σ) subunit N-terminal domain 1 (2), beta (β) subunit (3)
d. Sigma (σ) subunit C-terminal domain (1), sigma (σ) subunit N-terminal domain 1 (2), beta prime (β‘) subunit (3)
d.
Which two subunits of the RNA polymerase holoenzyme form a cleft that contains a deep channel down in which the DNA template binds?
a. sigma (σ) and omega (ω) subunits
b. sigma (σ) and beta prime (β‘) subunits
c. beta prime (β‘) and beta (β) subunits
d. beta (β) and sigma (σ) subunits
c.
This image shows the RNA Polymerase holoenzyme space-fill model. What is the approximate location of the active site?
a. location 1
b. location 3
c. location 2
d. location 4
b.
Magnesium ions (Mg++) are thought to play two roles in the function of the RNA polymerase holoenzyme:1) to promote the polymerization reaction to generate the RNA transcript and, 2) to bind and bend the DNA template.Where are these metal ions located on the RNA polymerase holoenzyme?
a. Two Mg++ ions are located in the active site.
b. Two Mg++ ions are located in the active site. Many other Mg++ ions coat the beta (β) and beta prime (β’) subunits.
c. Two Mg++ ions are located in the active site. Many other Mg++ ions coat the outside of the enzyme.
d. Many Mg++ ions coat the outside of the enzyme.
c.
Which of the following best characterizes the interactions between σ factor and a typical gene promoter in E. coli?
a. One α-helix from σ region 2 recognizes and binds the –35 element of the promoter and uses several of its aromatic amino acids to stabilize the melted DNA.
b. One α-helix from σ region 2 recognizes and binds the –10 element; a helix-turn-helix from σ region 4 recognizes and binds the –35 element; αCTD binds to the UP-element.
c. One α-helix from σ region 2 recognizes and binds the –10 element of the promoter and uses several of its aromatic amino acids to stabilize the melted DNA. A helix-turn-helix from σ region 4 recognizes and binds the –35 element.
d. One α-helix from σ region 2 recognizes and binds the –10 element; a helix-turn-helix from σ region 4 recognizes and binds the –35 element.
c.
