DNA Answer Key

1) The type of replication that occur in our cells is : A. Conservative B. Semi-conservative C. Dispersive D. None of the above 2) The structure of dATP is different from the ATP by : A. Base component B. Sugar component C. Phosphate group D. A and B 3) Who demonstrated that DNA is genetic material in T2 phage? A. Franklin B. Watson and crick C. Hershey and chase D. Chargaff 4) All of the following are functions of DNA polymerase except of : A. DNA Synthesis B. Primer synthesis C. DNA Proofreading D. DNA repair E. Replacement of RNA with DNA 5) Which of the following enzymes is not involved in nucleotide excision repair: A. Nuclease B. Ligase C. Primase D. DNA polymerase E. Both a and c ) Whi A. The C. The D. The h of the follo i g state e ts is true a out ’ e d of DNA : ’ e d has OH group B. The ’ e d has a phosphate group ’ e d is ide ti al to ’ e d ’ e d is the fifth positio o o e of the itroge ous ase 7) Synthesis of new DNA strand begins with : A. An RNA primer B. DNA primer C. Okazaki fragment D. Thymine dimer E. DNA ligase 8) The radioa ti e isotope P la els the T phage’s : A. DNA B. Tails C. Proteins D. Heat E. Base plate 9) Which of the following nitrogenous bases found in DNA but not in RNA? A. A B. G C. T D. C E. U 10) The short segments of newly synthesized DNA are joined into continuous strand by : A. Helicase B. DNA Polymerase C. Ligase D. Primase E. Single strand binding proteins 11) The first step of replication is catalyzed by : A. Helicase B. DNA Polymerase C. Ligase E. Single strand binding proteins D. Primase 12) An old DNA strand is used as ------------ for the assembly of new DNA strand : A. Complement B. Primer C. Model D. Template E. Source of nucleotide 13) Nucleic acids are assembled in ----------- direction : A. ’ to ’ B. ’ to ’ C. ’ to ’ D. ’ to ’ E. ’ to ’ 14) Which of the following is true about bacterial chromosome ? A. Single linear strand of DNA B. Double circular strand of DNA C. Single circular strand of DNA D. Double linear strand of DNA E. Double linear strand of RNA 15) Whi h of the follo i g is true a out ’ e d of DNA stra d : A. It consists of H atom B. it consists of OH group C. It consists of phosphate group D. it consists of nitrogen atom 16) If % of G= 22 , then the % of A = ? A. 28 % B. 22% C. 44% D. 66% E. None of the above 17) To repair thymine dimer by nucleotide excision repair , you need : A. Telomerase , Primase , DNA polymerase B. Telomerase , Helicase , single strand binding proteins C. Nuclease , DNA polymerase , DNA ligase D. DNA ligase , Replication fork proteins , Nuclease 18) In nucleotides , the nitrogenous base is attached to ----- carbon of the sugar , while the phosphate group is attached to -------- sugar . A. ’ ----- ’ B. ’ ----- ’ C. ’ ----- 5’ D. ’ ------ ’ 19) In complementary base pairing in double helix of DNA , Adenine pairs with ------ by -------------- : A. Thymine by three hydrogen bonds B. Guanine by two hydrogen bonds C. Thymine by two hydrogen bonds D. Cytosine with two hydrogen bonds 20) The enzyme that involved in replacement of RNA primers with DNA is : A. DNA poly III B. DNA poly I C. Ligase D. Helicase E. Primase 21) The best way for pairing the nitrogenous bases within the double helix is : A. Purine + Purine B. Purine + Pyrimidine C. Pyrimidine + Pyrimidine D. A and B is a correct pairing E. None of the following is true 22) The letter X shown in the figure equals : A. 0.34 nm B. 3.4 nm C. 1 nm D. 2 nm X 23) The letter y shown in the figure equals : A. 0.34 nm B. 3.4 nm C. 1 nm D. 2 nm 24) The scientists who demonstrated the double helix of DNA is : Answer : Watson and crick y 25) Which of the following true about lagging strand ? Answer : It needs only one primer – It is synthesized continuously 26) The enzyme that breaks , swivels , and rejoin the parental strands of DNA is : Answer : Topoisomerase 27) Which component is not directly involved in translation : A. mRNA b. DNA C. tRNA D. Ribosomes E. GTP 28) The enzyme responsible for removal of introns is : A. Splicesome B. Ligase C. Nuclease D. Ribozyme E. None of the above 29) Change a codon to a stop codon is called : A. Missense mutation B. Nonsense C. Frame shift D. Thymine dimer 0) The ’ e d od pre-mRNA is modified by addition of : A. A cap B. An intron C. A exon D. Poly-A tail E. Dose not modified 31) Processing of pre-mRNA into mRNA occur in : A. Cytoplasm B. Cytosol C. Nucleus D. Nucleolus 32) The start codon can be translate to ------- : Answer : Met E. None of the above 33) Which of the following is a stop codon ? Answer : UAA – UAG – UGA 34) The enzyme that responsible for transcription is : Answer : RNA polymerase II 35) The transcription factors can : Answer : Mediate the binding of RNA polymerase to the parental strand of DNA 36) Ribozymes are : Answer : RNA molecules that can function as enzymes 38) To start translation , the cell need ? Answer : GTP E–P–A 39) SRP molecules function involve : Targeting proteins to ER 40) In prokaryotic , translation occur : Immediately as soon as transcription occur 41) Polyribosome occur in eukaryotic when : mRNA simultaneously translated by several ribosomes 42) Frame shift mutations result from : Addition or deletion of nucleotides 1)S ickle cell disease result from ? Point mutation 2)N on-sense mutation cause ? Change the normal codon to a stop codon 3)W hich of the following compounds contain sulfur ? Proteins 4)W hich of the following protect mRNA from degradation ? 5’ ap a d poly-A tail 5)W hich of the following contain adenine ? RNA – DNA – ATP 6)W hich of the following prevent repairing of DNA strand ? Single strand binding proteins 7)W hich of the following is not property of DNA ? Anti-parallel Double helix Held by ionic bonds Pair with histones 8)S emi-conservative is a model found in ? DNA replication 9) Which of the following synthesis pre-mRNA in eukaryotic cells ? 10) The gene is ? Region of DNA produce polypeptide or RNA 11) The energy responsible for ATP production during cellular respiration ? Proton motive force 12) Which of the following is not part of electron transport chain between P680 and P700 ? Ferredoxin 13) The compound that used to fix carbon ? Ribulose bisphosphate 14) Which of the following responsible for production of NADH from NAD+ ? Reduction of acetaldehyde to ethanol 15) In addition to nucleus , DNA is found in ? Chloroplast and mitochondria 16) How many electrons are needed to passes electron transport chain to form one molecule of water ? 2 electrons 17) What is the purpose of beta oxidation ? Break down of fatty acids 18) Water passes quickly through cell membranes because ? It moves through aquaporin 19) Which is the molecule required to initiate translation ? GTP 20) During respiration .. C6H12O6 is oxidized and O2 reduced 20) Lysoso es a prese t i large u ers i ……… 21) I ele tro tra sport hai , NADH passes its ele tro s to ….. ? FMN 22) Which of the following organelles not found in animal cells ? Cell wall 23) If C=38% , then the T = ? 12 % 24) Which of the following false about exergonic reaction ? Product have higher energy than reactant 25) When plant cells placed in hypertonic solution they will ? Plasmolysis 26) The site at which the replication of DNA begins at is ? Origin of replication 27) The amino acid must remove their amine group at process celled ? Deamination 28) The membrane bound organelle which have enzyme to remove H from substrate and formation of Hydrogen peroxide is ? Peroxisome 29) The part of chlorophyll which absorbs light is ? Porphorin ring 30) What is the sequence that would a secretory proteins would passed ? Rough ER – Golgi – Cell membrane