Exam 2 Review Answers

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Exam Review
Week 6.3
Supplemental Instruction
Iowa State University
Leader: Natalie
Course: BIOL/GEN 313
Date: 10/13
Chapter: 12.1-12.4, 2.2, 13.1-13.4, 14.1-14.2
1. What is true about rolling circle replication
A. It does not require a break in the nucleotide strand
B. The products is one circular molecule
C. This form of replication takes place in F factor
2. Which of these types of replication is only bidirectional?
A. Rolling circle
B. Linear Eukaryotic
C. Theta
3. What would Meselson and Stahl have seen if DNA replication was conservative after two
rounds of replication?
A. Two bands corresponding to 14N and the other to 15N
B. One band corresponding to an intermediate weight
C. Two bands corresponding to an intermediate and the other to 14N
4. Which is true of the bands that were formed after two rounds of replication in the
Meselson Stahl experiment
A. The DNA separated to different densities: the upper band represents 15N and the
lower band 14N
B. The DNA separated in to different densities that suggested that DNA was conservative
C. The DNA separated according to heavy/intermediate/light densities according to the
distribution of original DNA to newly synthesized DNA
5. Which describes the second step of eukaryotic initation?
A. TBP subunit of TFIID bind to the TATA box
B. Basal Apparatus is formed, RNA pol II positioned over start site
C. Transcriptional Activator proteins bind regulatory promoter and enhancer
6. What is the correct order that the following appear in bacterial replication?
A. DNAa, DNA helicase, Pol 1, primase, ligase
B. DNA helicase, DNA gyrase, ligase, Tus protein
C. DNAa, primase, single stranded binding proteins, Tus protein
7. Where are consensus sequences?
A. The template strand
B. The Non-template strand
C. On the pre-mRNA
8. When is a free 3’ OH require for elongation?
A. To add a new nucleotide in DNA, not RNA
B. To add a new nucleotide in RNA, not DNA
C. To add a new nucleotide in both RNA and DNA
9. Where does discontinuous replication NOT always take place
A. The lagging strand
B. A strand in rolling circle replication
C. A strand in eukaryotic replication
10. Which is true about licensing?
A. Licensing occurs in both bacteria and eukaryotes
B. Licensing factor binds to the origin at G1 and is later removed by geminin
C. Licensing factor binds at G1 then degrades itself after initiation to prevent from
initiating replication more than once
11. Which would NOT be a result of excess telomerase?
A. Increased mammalian aging
B. Less shortening of telomeres
C. Shorter life span due to cancer
12. What consensus sequence is found in eukaryotes?
A. 5’-TATAAT-3’
B. 5’-TTGACA-3’
C. 5’-TATAAA-3’
13. Which class of RNA is correctly defined?
A. mRNA carries genetic code for proteins
B. rRNA helps incorporate amino acids into a polypeptide chain
C. tRNA is the structural and function components of the ribosome
14. What regions are in a bacterial transcription unit?
A. Enhancer, promoter, RNA-coding, terminator
B. Regulatory promoter, core promoter, RNA-coding, terminator
C. Promoter, RNA-coding, terminator
15. Where is upstream and downstream using the transcription start site as a reference?
A. Upstream is negatively numbered and before the start site, downstream is positive
B. Upstream is positively numbered and before the start site, downstream is negative
C. Upstream is negatively numbered and after the start site, downstream is positive
16. If a cell did not have functional primase what would occur?
A. No replication would take place
B. Theta replication would still take place
C. Rolling circle replication would still take place
17. In somatic cells the diploid number is 2. How many DNAs and chromosomes would
there be in M phase?
A. Two chromosomes and two DNAs
B. Four chromosomes and four DNAs
C. Two chromosomes and four DNAs
18. If sigma factor was mutated so it could not attach to the core what would you observe
about the initiation of transcription?
A. Nothing different, only the core is required
B. Initiation at random points on the DNA
C. No initiation of transcription
19. What is the third step of initiation in bacteria from the following?
A. Tight binding of the holoenzyme over the start site
B. Promoter escape
C. Weak binding of holoenzyme to -10 and -35
20. What is the effect of a missing consensus sequence?
A. Down mutation
B. Up mutation
C. Transcription would not occur
21. Introns
A. Sequences in the pre-mRNA that are present in the mature mRNA
B. Sequences that are spliced out of from pre-mRNA
C. Are rare in eukaryotic sequences
22. What does not cause transcriptional pausing?
A. Inverted repeats that form hairpins
B. Rho
C. String of A’s
23. Which is NOT a form of bacterial termination
A. Rho-independent
B. Rat 1
C. Rho-dependent
24. What recognizes eukaryotic promoters?
A. The core promoter
B. The holoenzyme
C. accessory proteins
25. What is the correct placement of the following in eukaryotic transcription?
A. Enhancer, regulatory promoter, core promoter
B. Enhancer, core promoter, regulatory promoter
C. Regulatory promoter, core promoter, enhancer
26. What makes up the basal transcription apparatus?
A. Transcriptional activator proteins, RNA pol II, mediator
B. Transcription factors, RNA pol II, mediator
C. Transcriptional activator proteins, RNA pol II, enhancers
27. What binds to the TATA box?
A. TBP subunit of TFIID
B. Basal transcription apparatus
C. Enhancers
28. Which is true about colinearity?
A. Bacterial genes are not colinear
B. Eukaryotic genes are colinear
C. A continuous sequence of nucleotides in the DNA codes for a continuous sequence of
amino acids in a protein
29. What is true about polycistronic RNA?
A. Often occurs in eukaryotic RNA
B. A transcription unit has a single gene
C. A group of genes is transcribed into a single RNA
30. What does a regulatory promoter bind?
A. Transcriptional activator proteins
B. Transcriptional factors
C. RNA pol II
31. Which is NOT true about eukaryotic termination?
A. Rat 1 digests DNA causing the pre-mRNA to fall off
B. Cleavage site determined by consensus sequence
C. Pre-mRNA is cleaved off while RNA pol II is still transcribing
32. What regions are in a mature mRNA?
A. Promoter, RNA-coding, terminator
B. RNA coding, terminator
C. 5’ UTR, protein coding, 3’ UTR
33. How many major types of introns are there?
A. 2
B. 3
C. 4
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