DC bio unit 6 test

1) A particular triplet of bases in the template strand of DNA is 5' AGT 3'. The corresponding codon for the mRNA transcribed is

A) 3'-UCA-5'

24. Which of the following statements best describes the characteristics of siRNA

A) a double stranded rna one of whose strands can complement and inactivate a sequence of mRNA

3. WHich of the following statements best supports the one gene-one enzyme hypothesis?

A) a mutation in a single gene can result in a defective protein

14. The anticodon of a particular tRNA molecule is

A) complimentary to the corresponding mRNA codon

16. If a mutation deactivated a regulatory gene of a repressible operon in an e. coli cell, which of the following describes the most likely outcome

A) continuous transcription of the structural gene controlled by that regulator

31. When attempting to introduce a particular fragment of DNA into the genome of an animal cell, which of the following methods would be most successful

A) crispr/cas9 recombination

11. What is the function of the release factor during translation in eukaryotes

A) it binds to the stop codon in the A site in place of tRNA

32. Which of the following characteristics of taq polymerase make it useful in the pcr process

A) it is heat stable and can withstand the heating step of pcr

28. Which of the following outcomes could be achieved using RNAi methodology

A) reduction in protein produced from a gene of interest

22. Which of the following functions are characteristic of general transcription factors in eukaryotes

A) they bind to other proteins or to the tata box

30. They are eukaryotic cells. Which order of the following steps provides the most logical sequence to follow when splicing foreign DNA into a plasmid and inserting the plasmid into a bacterium

B) 3, 2, 4, 5, 1

7. Which of the following processes correctly describes alternative RNA splicing?

B) It can allow the production of proteins of different sizes and functions from a single mRNA

5. In eukaryotes, there are several different types of RNA polymerase. Which type is involved in transcription of mRNA for a protein

B) RNA polymerase II

23. Which of the following results is most likely to occur if acetylation of histone tails in the chromatin of embryonic cells is increased

B) decreased chromatin condensation

35. Which of the following statements correctly describes one of the main differences between embryonic stem cells and adult stem cells

B) embryonic stem cells can give rise to all cell types in the organism, and adult stem cells cannot

40. In large-scale, genome-wide association studies in humans, which of the following types of genetic markers are typically sought by researchers

B) specific SNPs found more often in persons with a particular disorder than in healthy controls

19. Under what conditions does the trp repressor block transcription of the trp operon

B) when the repressor binds to tryptophan

39. Which of the following characteristics of retroviruses most directly contributes to their usefulness in gene therapy applications?

C) DNA copies of retroviral genomes become integrated into the genome of the infected cell

18. For a repressible operon to be transcribed, which of the following conditions must occur

C) RNA polymerase must bind to the promoter, and the repressor must be inactive

26. A cell is considered to be differentiated if it has which of the following characteristics?

C) The cell produces proteins specific to a particular cell type

27. Which of the following types of mutation would convert a proto oncogene into an oncogene

C) a mutation that greatly increases the amount of the proto oncogene protein

9. During the elongation phase of translation, which site in the ribosome represents the first location where a codon pairs with an anticodon

C) a-site

21. DNA methylation and histone acetylation are examples of which of the following processes.

C) epigenetic phenomena

10. Which of the following statements describes the effect of a nonsense mutation on a gene

C) it introduces a premature stop codon into the mRNA

4. According to the central dogma, which of the following intermediate molecules correctly completes the flowchart describing the flow of information in a cell blank?

C) mRNA

17. Which of the following conditions is most likely to result in transcription of the lac operon

C) the cAMP and lactose levels are both high within the cell

34. The cloning of dolly the sheep is an example of which of the following processes

C) transfer of an adult cell's nucleus into an enucleated sheep egg, followed by incubation in a surrogate

13. Which of the following mutations would be most likely to have a harmful effect on an organism

D) a single nucleotide insertion downstream of, and close to, the start of the coding sequences

20. If a researcher moves the promoter for the lac operon to the region between the beta galactosidase gene and the permease gene, which of the following results would be most likely?

D) beta galactosidase will not be produced

33. Which of the following correctly lists the processes in order for one cycle of polymerase chain reaction PCR

D) denature dna; anneal primers; extend primers

6. RNA is single stranded, can hydrogen bond with other nucleic acids, and has functional groups that can function in catalysis. These characteristics support that RNA could have which of the following cellular roles?

D) forming peptide bonds

2. What amino acid sequence will be generated based on the following mRNA codon sequence

D) met-ser-ser-leu-ser-leu

36. In animals, what is the difference between reproductive cloning and therapeutic cloning?

D) only therapeutic cloning supplies cells for repair of diseased or injured organs

25. The product of the bicoid gene in drosophila is responsible for determining which of the following embryonic features or structures during development

D) orientation of the anterior posterior axis

15. Which of the following molecules is a protein produced by a regulatory gene

D) repressor

38. Which of the following best describes a biological concern regarding the use of CRISPR-Cas9 gene editing in humans

D) the modifications created by the process may result in unintended effects on non-target genes

12. In eukaryotes, which of the following is the first step in translation?

D) the small subunit of the ribosome recognizes and attaches to the 5' cap of mRNA

29. Which of the following characteristics best support using yeast cells instead of bacterial cells to express mammalian proteins via cloning?

D) they are eukaryotic cells

37. The first cloned cat, called carbon copy, was a calico, but she looked significantly different from her female parent. Which of the following best explains the reason for the differences?

D) x chromosome inactivation in the embryo is random and produces different patters

8. Which of the following processes will occur at the exposed 3' end of a tRNA molecule?

a) an amino acid will bind covalently