Chapter 29

Question 1

Differences in DNA and RNA synthesis.

Answer 1

the nature of the nucleotide used
the need for a primer
the presence of discrete termination signals
the simultaneous coding from both strands of DNA

Question 2

During transcription, separation of the DNA strands is necessary. This involves:

Answer 2

separation in only a small segment of DNA at a time.

Question 3

In prokaryotic organisms, translation of the mRNA begins

Answer 3

while the transcription process is still in progress.

Question 4

Which of the following is NOT seen in the editing of RNA in eukaryotes

Answer 4

adding a poly(A) tail to the 5′ end

Question 5

The removal of introns during splicing is catalyzed by

Answer 5

RNA molecules associated with the spliceosomes.

Question 6

Which of the following describes the mechanisms of rifampicin and actinomycin D?

Answer 6

Rifampicin blocks the channel for the RNA-DNA hybrid, and actinomycin D binds to double-stranded DNA.

Question 7

Which of the following processing events takes place between the time the pre-rRNA is transcribed and when 18S, 28S, and 5.8S rRNAs are assembled with ribosomal proteins into the ribosomal subunits 40S and 60S?

Answer 7

methylation of ribose

Question 8

Unlike prokaryotic tRNA transcripts, eukaryotic tRNA transcripts undergo

Answer 8

splicing to remove an intron

Question 9

Which of the following components of pre-mRNA is NOT generated from a DNA template?

Answer 9

poly(A) tail

Question 10

RNA editing:

Answer 10

takes place after transcription but before translation.
is a distinct process from RNA splicing.
can result in different forms of the same protein in different cell types.
might involve the chemical modification, such as deamination, of bases.

Question 11

Splicing

Answer 11

occurs at a faster rate due to enzymes called snRNPs.

Question 12

At least 15% of all genetic diseases are due to mutations that affect mRNA

Answer 12

Splicing

Question 13

different between prokaryotic and eukaryotic transcription processes?

Answer 13

extensive processing of the mRNA prior to translation in eukaryotes
transport of the mRNA across a membrane prior to translation in eukaryotes
transcription frequency is controlled by a complex set of transcription factors in eukaryotes
eukaryotic promoter elements are often much further away from the transcription start site.

Question 14

Group I introns

Answer 14

Are ribozymes