Quick Biochemistry - Nucleic Acids (Section 6)

  • 1
    Which of the following is NOT a characteristic of orotic aciduria?
    პასუხი
    (A)
    Enhanced production of pyrimidine nucleotides
  • 2
    A genetic lack of adenosine deaminase leads to
    პასუხი
    (C)
    Weakened immune system
  • 3
    A total lack of hypoxanthine guanine phospharibosyl transferase results in
    პასუხი
    (D)
    Lesch-Nyhan syndrome
  • 4
    Increased excretion of orotic acid in urine can be caused by a deficiency in
    პასუხი
    (D)
    Any of the options listed
  • 5
    Which of the following is NOT a typical symptom of Lesch-Nyhan syndrome?
    პასუხი
    (C)
    Delayed growth
  • 6
    A hereditary deficiency in purine nucleoside phosphorylase is most likely to cause
    პასუხი
    (C)
    Immune system problems
  • 7
    Deoxyribonucleotides are produced through the reduction of
    პასუხი
    (C)
    Ribonucleoside diphosphates
  • 8
    What other compound can orotate phosphoribosyl transferase use?
    პასუხი
    (D)
    Adenine
  • 9
    Why is gout less common in mammals other than higher primates?
    პასუხი
    (D)
    They have uricase enzyme
  • 10
    Low levels of uric acid can occur in individuals with
    პასუხი
    (A)
    Xanthine oxidase deficiency
  • 11
    The process of creating a DNA copy is also termed
    პასუხი
    (B)
    Replication
  • 12
    The method by which DNA is replicated is described as
    პასუხი
    (B)
    Semi-conservative
  • 13
    In what direction is new DNA generally assembled
    პასუხი
    (A)
    5' to 3'
  • 14
    In the DNA synthesis process, what usually comes before
    პასუხი
    (A)
    Replication
  • 15
    Short segments found in DNA replication consist of
    პასუხი
    (C)
    Both RNA and DNA
  • 16
    Which of the following molecules has its assembly that results in Okazaki fragments
    პასუხი
    (D)
    DNA
  • 17
    When the replication fork appears
    პასუხი
    (B)
    One strand is made continuously, the other with breaks
  • 18
    About how many units make up one Okazaki fragment
    პასუხი
    (C)
    1,000 Units
  • 19
    Which enzyme is responsible for creating the RNA primer
    პასუხი
    (B)
    Primase
  • 20
    In RNA, what base pairs with adenine
    პასუხი
    (D)
    Uracil
  • 21
    In the process of duplication, where does the original DNA strand separate?
    პასუხი
    (C)
    At several locations
  • 22
    In DNA replication, what molecule initiates the separation of the double helix?
    პასუხი
    (B)
    DnaB protein
  • 23
    To separate the double-stranded DNA, what is needed?
    პასუხი
    (A)
    Energy from ATP
  • 24
    What action do helicase and DnaB protein perform?
    პასუხი
    (C)
    Unwinding DNA and requires ATP
  • 25
    After the DNA strands separate, how are they kept apart?
    პასუხი
    (A)
    Single strand binding protein
  • 26
    What enzyme adds deoxyribonucleotides to the RNA primer?
    პასუხი
    (C)
    DNA polymerase III holoenzyme
  • 27
    Which enzyme replaces the RNA primer's ribonucleotides with deoxyribonucleotides?
    პასუხი
    (A)
    DNA polymerase I
  • 28
    What is used to join DNA fragments together?
    პასუხი
    (B)
    DNA ligase
  • 29
    What introduces negative supercoils into the DNA structure?
    პასუხი
    (C)
    DNA gyrase
  • 30
    Which of the following contains reverse transcriptase activity in eukaryotic cells?
    პასუხი
    (C)
    Telomerase
  • 31
    What function does the DNA polymerase III holoenzyme perform?
    პასუხი
    (D)
    3'→5' Exonuclease and polymerase activities
  • 32
    What is a characteristic function of DNA polymerase I?
    პასუხი
    (D)
    All of these
  • 33
    What is the role of the 3'→5' Exonuclease activity of DNA polymerase I?
    პასუხი
    (C)
    Corrects errors in replication
  • 34
    Which of the following statements about RNA-dependent DNA polymerase is incorrect?
    პასუხი
    (D)
    It is present in all the viruses
  • 35
    What reaction does reverse transcriptase facilitate?
    პასუხი
    (C)
    Synthesis of DNA
  • 36
    What type of DNA does the DNA A protein specifically bind to?
    პასუხი
    (B)
    Negatively supercoiled DNA
  • 37
    What reaction does DNA topoisomerase I of E. coli catalyze?
    პასუხი
    (A)
    Relaxation of negatively supercoiled DNA
  • 38
    During which phase of the mammalian cell cycle does DNA synthesis take place?
    პასუხი
    (A)
    S phase
  • 39
    At what temperature does the melting of DNA occur?
    პასუხი
    (D)
    Native double helical DNA is denatured
  • 40
    What factor increases the melting temperature of DNA?
    პასუხი
    (B)
    G and C content
  • 41
    The factor that enhances the buoyant density of DNA is related to its
    პასუხი
    (B)
    Guanine and Cytosine base composition
  • 42
    The ratio of Guanine and Cytosine to Adenine and Thymine within DNA can be calculated by examining its
    პასუხი
    (C)
    Both methods
  • 43
    Mitochondria in certain cell types contain some amount of DNA in
    პასუხი
    (B)
    More complex cells
  • 44
    Which characteristic is observed in satellite DNA?
    პასუხი
    (A)
    Highly recurring sequences
  • 45
    What is the process of creating RNA using a DNA blueprint called?
    პასუხი
    (C)
    RNA creation
  • 46
    In which direction is RNA generally synthesized?
    პასუხი
    (A)
    Five prime to three prime
  • 47
    DNA-dependent RNA polymerase has how many protein subunits?
    პასუხი
    (D)
    Four
  • 48
    For effective operation, DNA-dependent RNA polymerase requires
    პასუხი
    (C)
    Either ion
  • 49
    Which element identifies the transcription starting point?
    პასუხი
    (C)
    Sigma factor
  • 50
    The location where transcription concludes is determined by
    პასუხი
    (D)
    Rho factor