* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download SBI4U Molecular genetics UNIT_AK
Nutriepigenomics wikipedia , lookup
Epigenetics of human development wikipedia , lookup
Nucleic acid tertiary structure wikipedia , lookup
Transcription factor wikipedia , lookup
Cancer epigenetics wikipedia , lookup
Polyadenylation wikipedia , lookup
Genomic library wikipedia , lookup
United Kingdom National DNA Database wikipedia , lookup
Genealogical DNA test wikipedia , lookup
SNP genotyping wikipedia , lookup
No-SCAR (Scarless Cas9 Assisted Recombineering) Genome Editing wikipedia , lookup
DNA damage theory of aging wikipedia , lookup
Bisulfite sequencing wikipedia , lookup
Frameshift mutation wikipedia , lookup
DNA vaccination wikipedia , lookup
Molecular cloning wikipedia , lookup
Gel electrophoresis of nucleic acids wikipedia , lookup
History of RNA biology wikipedia , lookup
DNA polymerase wikipedia , lookup
Epigenomics wikipedia , lookup
Extrachromosomal DNA wikipedia , lookup
History of genetic engineering wikipedia , lookup
Nucleic acid double helix wikipedia , lookup
Non-coding RNA wikipedia , lookup
Microevolution wikipedia , lookup
Cell-free fetal DNA wikipedia , lookup
DNA supercoil wikipedia , lookup
Messenger RNA wikipedia , lookup
Vectors in gene therapy wikipedia , lookup
Genetic code wikipedia , lookup
Non-coding DNA wikipedia , lookup
Cre-Lox recombination wikipedia , lookup
Epitranscriptome wikipedia , lookup
Helitron (biology) wikipedia , lookup
Artificial gene synthesis wikipedia , lookup
Nucleic acid analogue wikipedia , lookup
Point mutation wikipedia , lookup
Therapeutic gene modulation wikipedia , lookup
K: ___/22 T:___/10 C:___/8 Total: ____/54 = _____% A:___/14 Name: _____________________________ SBI4U Unit Test: Molecular Genetics Multiple Choice (K/17) ___ 1.Which of the following terms does not describe DNA replication? a. uni-lateral c. bi-directional b. semi-discontinuous d. semi-conservative ___ 2. The central dogma of molecular biology states that the information in DNA is copied to _______ by the process of __________, and then to ___________ via____________. a. protein, transcription, RNA, translation b. RNA, transcription, protein, translation c. RNA, translation, protein, transcription d. protein, translation, RNA, transcription ___ 3. Pairs of homologous chromosomes line up along the equator of the cell in: a. Prophase I c. Metaphase I b. Prophase II d. Metaphase II ___ 4. The universal start codon also encodes: a. does not code an A.A. c. threonine b. leucine d. methionine ___ 5.Two alleles for fur colour exist in a population of mice: B (dominant brown) and b (recessive white). If the allele frequency of b is 0.34, what proportion of the mouse population will be heterozygous (Bb)? a. 0.12 c.0.45 b. 0.34 d. 0.66 ___ 6.A base-pair substitution can be classified as all of the following, except: a. nonsense mutation c. silent mutation b. frameshift mutation d. missense mutation ___ 7.Which of the following genes is not under the control of the lac operator? a. LacI c. LacZ b. Lac X d. LacY ___ 8.Chinchillas have 32 pairs of chromosomes. After a round of mitotic division, how many chromosomes will each daughter cell contain? a. 16 c. 64 b. 32 d. 128 Page 1 of 7 K:___ T:___ C:___ A:___ ___ 9. Gel electrophoresis is a method for separating DNA fragments according to their size. When electrophoresed, DNA fragments will migrate at a rate that is: a. proportional to their size b. proportional to the logarithm of their size c. inversely proportional to their size d. inversely proportional to the logarithm of their size ___ 10.Which of the following is true about the bonding in a DNA molecule? a. The sugar-phosphate backbone is joined by hydrogen bonds b. The sugar-phosphate backbone is joined by phosphodiester bonds c. The nitrogenous bases are joined by phosphodiester bonds d. The nitrogen bases are joined by glycosyl bonds ___ 11. The synthesis of Okazaki fragments occurs because: a. DNA strands run antiparallel, and synthesis can only occur in the 3’ 5’ direction. b. DNA strands run antiparallel, and synthesis can only occur in the 5’ 3’ direction. c. RNA primase as a high affinity for the lagging strand, and primes it often d. There is only enough free energy to synthesize one strand continuously ___ 12.Which of the following post-transcriptional modifications is carried out in a prokaryotic cell? a. 5’ cap of 7-methyl guanosine and 3’ poly-A tail are added b. introns are spliced out, and exons are ligated c. both a and b d. neither a nor b ___ 13. In eukaryotes, what part of the mRNA transcript is recognized by the ribosome so it knows to assemble? a. Shine-Dalgarno sequence c. the 3’ poly-A tail b. the promoter d. the 5’ cap ___ 14. During protein synthesis, the ribosome moves along the mRNA in groups of ______ bases, called ______. A tRNA with a complementary _______ delivers the amino acid. a. three; codons; anticodon b. three; anticodons; codon c. four; codons; anticodon d. four; anticodons; codon Page 2 of 7 K:___ T:___ C:___ A:___ ___ 15.A particular operon is controlled by a repressor. It is not transcribed in the presence of protein X. When concentrations of protein X decline, transcription of the operon occurs. Which statement describes the situation best? a. this is positive regulation, and protein X is the effector b. this is positive regulation, and protein X is the regulator c. this is negative regulation, and protein X is the effector d. this is negative regulation, and protein X is the promoter ___ 16. SalI is a restriction enzyme that recognizes the following sequence, and cuts between the G and the T: 5’-GTCGAC-3’ 3’-CAGCTG-5’ What type of ends are formed by cleavage with SalI? a. split end b. 5’ overhang sticky end c. 3’ overhang sticky end d. blunt end ___ 17. Which of the following is not an application of RFLP? a. genetic screening c. forensic identification b. bacterial transformation d. paternity testing Short answer 18. Look at the following picture of an agarose gel following electrophoresis of the four samples in a Sanger sequencing reaction. (T/2) a. What is the sequence of DNA? 5’-GTACATTAAA-3’ b. Label the end with positive electrode (+), and the negative electrode (-). (-) (+) Page 3 of 7 K:___ T:___ C:___ A:___ 19. DNA replication has proofreading mechanisms whereas transcription does not. Describe two reasons why a cell can more easily tolerate an error in transcription. (C/2) Description of any two of the following: Error is not inherited Normal proteins should outnumber defective proteins Redundancy of the genetic code Wobble base pairing 20 a. Compare the processes of DNA replication, Polymerase Chain Reaction, and transcription: (K/3) Replication ____ separates Type of primer the DNA strands helicase RNA Enzyme that synthesizes the new strand DNA Pol III PCR Heat DNA DNA Pol (Taq polymerase) Transcription RNA polymerase None RNA polymerase b. PCR does not require single stranded binding proteins, or a DNA gyrase. What purpose does each of these molecules serve in DNA replication, and why are they not required in PCR? (C/3) SSB – keeps strands from re-annealing DNA gyrase – relieves torsional strain caused of strands unwinding Not required bc heat completely denatures the strands from each other 21. This picture depicts transcription and translation in a cell. Is this cell prokaryotic, or eukaryotic? How do you know? (A/2) Prokaryotic coupled transcription-translation Page 4 of 7 K:___ T:___ C:___ A:___ 22.An individual is homozygous at two loci: A/a·B/b. a. Write out the four possible combinations of alleles (T/1) AB, ab Ab, aB b. What proportion of each gamete can be expected if loci A and B are unlinked? (T/1) 25% of each Suppose the individual described above received the following combinations of alleles from its parents: A·B from its mother, a·b from its father. c. Rewrite the allele combinations from (a). What proportion of each gamete can be expected if loci A and B experience a recombination frequency of 0.2? (T/1) AB – 40% ab – 40% Ab – 10% aB – 10% 23 a. List the four levels at which gene regulation can act (K/2) Transcriptional, post-transcriptional, translational, post-translational b. In gene therapy, antisense oligonucleotides act by bonding to targeted mRNA’s in order to prevent their products from being made. At what level is this form of gene regulation acting? (A/1) Translational 24. Describe either the experiment of either Meselson and Stahl, or Beadle and Tatum: What did they do, what did they see, and what did they conclude? (C/3) Check notes – One mark for each point Page 5 of 7 K:___ T:___ C:___ A:___ 25. Considering the following DNA sequence: 3’ – CCGTACCCTGTATAAAAC – 5’ a. Write the complementary DNA strand that would be produced in replication (A/1): 3’ – CCGTACCCTGTATAAAAC – 5’ 5’ – GGCATGGGACATATTTTG – 3` b. Write the complementary mRNA strand that would be produced in transcription (A/1): 3’ – CCGTACCCTGTATAAAAC – 5’ 5’ – GGCAUGGGACAUAUUUUG – 3` c. What is the sequence of amino acids that would result from translation of the mRNA sequence? (A/1) GLY – MET – GLY – HIS – ILE - LEU The Genetic Code (the pocket version): Codon AAC AUG AUU CCG CAU CUU Amino acid Asn Met Ile Pro His Leu Codon GAC GGA GGC UAA UCA UUG Amino acid Asp Gly Gly Stop Ser Leu Bonus: (K/1) What was the name of the scientist who actually performed the experiment that produced the X-ray crystallography image of DNA? rosalind franklin Page 6 of 7 K:___ T:___ C:___ A:___ 26. Consider the following mRNA sequence, and the polypeptide produced as a result: 5’ - AUG Met mRNA: polypeptide: AAC Asn CCC Pro ACA Thr UAA - 3’ stop A mutation occurs so that the following mRNA is transcribed: mRNA: polypeptide: 5’ – AUG UAA Met STOP CCC CAC AUA- 3’ a. Is this a base pair substitution, insertion, or deletion? (T/1) insertion b. Use the genetic code from #25 to translate the polypeptide sequence, and write it in above (T/1) c. Is this a nonsense, missense, or a silent mutation? (T/1) nonsense 27. A DNA fragment that is 1000 bp long is analyzed. Its composition is found to be 32% thymine. How many guanines bases are in the fragment? (T/2) Guanine – 18% 18% x 1000 = 180 *Note should be 18% x 2000 = 360 since each base pair contains 2 bases, but I forgot to point this out when taking up the sheet. I accept either answer. Matching (A/8) For each of the following items, indicate in which process they are found. Do this by writing in the letters corresponding to the process next to the component. Processes: A. DNA replication B. Transcription C. Translation D. PCR _D__ 28. DNA primers _D__ 32. heat denaturation _C__ 29. small and large ribosomal subunits _A__ 33. DNA gyrase _B__ 30. RNA polymerase _D__ 34. Taq polymerase _C__ 31. transfer RNA ___ 35. RNA polymerase Page 7 of 7 K:___ T:___ C:___ A:___