CH.26 achieve adaptive quiz

What is the function of the cAMP receptor protein?

In the absence of glucose, it increases the transcription of genes coding for enzymes that metabolize alternate sugars.

What term refers to catalytic RNA?

ribozyme

All RNA viruses, except retroviruses, must express _____ polymerases to replicate in the host cell.

RNA-dependent RNA

What revelation(s) resulted from the purification of spliceosome snRNP components and identification of the associated snRNAs?

generate antibodies

Synthetic DNA that is generated using mRNA as a template is called:

cDNA

How do RNA tumor viruses cause cancer?

They contain oncogenes that cause host cells to grow abnormally.

Which statement is false regarding E. coli tRNA?

• Alternative splicing of the pre-rRNA transcript (30S) produces mature tRNA.

• RNase P, an endonuclease, removes RNA at the 5′ end of tRNAs.

• There are multiple copies of many of the 40 to 50 distinct tRNA genes.

• The 3′-terminal trinucleotide CCA(3′) is added during processing.

• Each of the seven pre-rRNA molecules codes for a different tRNA in the segment between the 16S and 23S rRNA genes.

There are multiple copies of many of the 40 to 50 distinct tRNA genes.

Many vaccines are made from viral envelope proteins. What feature of HIV complicates the development of an effective vaccine against the virus?

HIV reverse transcriptase has a very high error rate.

Which statement is false regarding the role of Mg²⁺ in the activity of RNA polymerase activities?

• The two Mg²⁺ ions interact with two phosphate groups on the incoming NTP.

• One Mg²⁺ ion facilitates displacement of the pyrophosphate from the incoming NTP.

• One Mg²⁺ ion facilitates the attack by the growing chain's 5′-hydroxyl group on the β phosphate of the incoming NTP.

• The two Mg²⁺ ions interact with three highly conserved Arg residues in the enzyme.

One Mg²⁺ ion facilitates the attack by the growing chain's 5′-hydroxyl group on the β phosphate of the incoming NTP.

Which DNA strand is identical to the 5′→3′ RNA strand, EXCEPT for having thymine in lieu of uracil?

5′→3′ template strand

3′→5′ nontemplate strand

3′→5′ template strand

5′→3′ nontemplate strand

5′→3′ nontemplate strand

Which cellular RNAs undergo posttranscriptional processing?

mRNA, tRNA, and rRNA

Which statement is false about telomerase?

• It acts as a cellular reverse transcriptase that provides the active site for RNA-dependent DNA synthesis.

• It uses the 3′ end of a chromosome as primer.

• It has a T_xG_y repeat that acts as a template for telomere synthesis.

• It is a ribonucleoprotein.

It has a T_xG_y repeat that acts as a template for telomere synthesis.

A few bacterial and archaeal genes have introns. Which type(s) of intron do these rare bacterial genes contain?

group I and group II

What viral component is utilized in making many modern vaccines?

the proteins of the viral envelope used to make one or 2 coatings

In the search for a ribozyme that can catalyze its own synthesis, which ribozymes cross-catalyze each other's formation?

E and E′

Which enzyme is NOT required to extend chromosomal telomeres?

DNA polymerase

DNA helicase

telomerase

RNA primase

DNA ligase

DNA helicase

What is the first step in the reverse transcriptase process to incorporate viral RNA into the host's genome?

synthesize a complementary DNA strand using the viral RNA as a template

Another name for RNA replicase is:

RNA-dependent RNA polymerase.

What substrates do ribozymes act on in their catalytic reactions?

RNA

Which Pol II transcription factor plays a role in the initiation complex?

elongin

SII

TBP

pTEFb

ELL

TBP

Which mutation is a silent mutation?

GAU to GAA

UUC to UUA

GCG to GCU

AGU to AGA

GCG to GCU

Which mutation would cause translation to terminate prematurely?

UGA to UAA

UAC to UAG

UUA to UUC

AUA to AUG

UAC to UAG

How does protein synthesis differ in bacteria and eukaryotes?

In bacteria, but not eukaryotes, transcription and translation occur simultaneously.

Which amino acid is MOST likely to be found in the hydrophobic core of a signal sequence?

Val

Arg

Asp

Glu

Val

Which arm of a tRNA molecule mediates interactions between the tRNA and the large-subunit rRNA?

anticodon arm

TψC arm

D arm

amino acid arm

TψC arm

What is the function of caveolin?

It causes invaginations in lipid raft-containing membranes.

Which mutation would cause a shift in the reading frame during translation?

deletion of one nucleotide and insertion of two nucleotides in adjacent codons

Which structure must bind to a nuclear protein before it can pass through the nuclear pore complex?

NTF2

Ran-GTP

importin α and importin β

CAS

importin α and importin β