1|Page
Cell Bio Exam 3 Dimario, chapter
7 Test with Answers Graded A+
This is a region is a gene that is a transcriptional control region... Ans:
Promoter
What is a gene? Ans: •the entire DNA sequence necessary for the production
of a functional protein or RNA.
- mRNAs that encode proteins
- ribosomal, transfer, and other functional
RNAs as well (i.e., non-coding RNAs)
• includes transcriptional control regions (promoters)
• includes introns and exons.
,2|Page
• includes enhancer sequences that could lie some distance
away from the promoter, either upstream or downstream.
Mono-cistronic mRNAs (eukaryotic mRNAs) Ans: In Eukaryotes: pre-mRNAs
w/introns
Poly-cistronic mRNAs (prokaryotic mRNAs) Ans: The operon but no introns in
prokaryotes
Introns are Ans: noncoding DNA sequences,
•Extremely rare in prokaryotes.
• Yeast have introns, but not as prevalent as in higher eukaryotes.
• Higher animals and plants have plenty of introns.
What is one way of yielding different protein products from a single pre-
mRNA? Ans: Alternative Splicing
What are three different mechanisms of alternative splicing? Ans: - Different
internal splicing
, 3|Page
- Different 3' ends
- Different 5' ends
(These could be produced by two different promoters, perhaps early versus
late in development)
True or False? The human genome contains a lot of intergenic DNA. Ans:
TRUE
True or False? The yeast gene contains a lot of intergenic DNA and introns.
Ans: FALSE, the yeast genome contains very little intergenic DNA and
relatively few introns.
What are pseudogenes? Ans: these are genes that arise by reverse
transcription of the mature mRNA (e.g. upon retroviral infection)
- no promoter, no introns (they are silent)
Why is there so much non-functional/non-coding DNA? (explains the
paradox) Ans: Repetitive DNA sequences
Whats the C-value paradox? Ans: why do the C values do not correlate with
phylogeny?
These are genes that encode functionally related, homologous proteins or
RNAs... Ans: Gene Families
Unequal crossing-over between what kind of elements resulted in the initial
duplication of an ancestral globin gene? Ans: L1 (LINE 1) elements
Cell Bio Exam 3 Dimario, chapter
7 Test with Answers Graded A+
This is a region is a gene that is a transcriptional control region... Ans:
Promoter
What is a gene? Ans: •the entire DNA sequence necessary for the production
of a functional protein or RNA.
- mRNAs that encode proteins
- ribosomal, transfer, and other functional
RNAs as well (i.e., non-coding RNAs)
• includes transcriptional control regions (promoters)
• includes introns and exons.
,2|Page
• includes enhancer sequences that could lie some distance
away from the promoter, either upstream or downstream.
Mono-cistronic mRNAs (eukaryotic mRNAs) Ans: In Eukaryotes: pre-mRNAs
w/introns
Poly-cistronic mRNAs (prokaryotic mRNAs) Ans: The operon but no introns in
prokaryotes
Introns are Ans: noncoding DNA sequences,
•Extremely rare in prokaryotes.
• Yeast have introns, but not as prevalent as in higher eukaryotes.
• Higher animals and plants have plenty of introns.
What is one way of yielding different protein products from a single pre-
mRNA? Ans: Alternative Splicing
What are three different mechanisms of alternative splicing? Ans: - Different
internal splicing
, 3|Page
- Different 3' ends
- Different 5' ends
(These could be produced by two different promoters, perhaps early versus
late in development)
True or False? The human genome contains a lot of intergenic DNA. Ans:
TRUE
True or False? The yeast gene contains a lot of intergenic DNA and introns.
Ans: FALSE, the yeast genome contains very little intergenic DNA and
relatively few introns.
What are pseudogenes? Ans: these are genes that arise by reverse
transcription of the mature mRNA (e.g. upon retroviral infection)
- no promoter, no introns (they are silent)
Why is there so much non-functional/non-coding DNA? (explains the
paradox) Ans: Repetitive DNA sequences
Whats the C-value paradox? Ans: why do the C values do not correlate with
phylogeny?
These are genes that encode functionally related, homologous proteins or
RNAs... Ans: Gene Families
Unequal crossing-over between what kind of elements resulted in the initial
duplication of an ancestral globin gene? Ans: L1 (LINE 1) elements