Quick Biochemistry - Nucleic Acids (Section 1)

  • 1
    What components combine to form a nucleoside?
    پاسخ دهید
    (B)
    A purine or pyrimidine base and a sugar
  • 2
    Which of the following best describes the composition of a nucleotide?
    پاسخ دهید
    (B)
    A purine and pyrimidine base, a sugar, and phosphorous
  • 3
    Which of the following is classified as a purine nucleotide?
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    (A)
    AMP
  • 4
    Which option represents a pyrimidine nucleotide?
    پاسخ دهید
    (C)
    CMP
  • 5
    Adenine is also known as:
    پاسخ دهید
    (A)
    6-Amino purine
  • 6
    What is the other name for 2, 4-Dioxypyrimidine?
    پاسخ دهید
    (C)
    Uracil
  • 7
    What is the chemical designation for guanine?
    پاسخ دهید
    (B)
    2-Amino-6-oxypurine
  • 8
    In what units are the concentrations of nucleotides and nucleic acids frequently expressed?
    پاسخ دهید
    (D)
    OD at 260 nm
  • 9
    Which pyrimidine nucleotide is involved in high-energy intermediate reactions?
    پاسخ دهید
    (C)
    UDPG
  • 10
    In a nucleotide, what carbon position on the pentose molecule is involved in an ester bond with phosphate?
    پاسخ دهید
    (D)
    C₅
  • 11
    What molecule results from the combination of uracil and ribose?
    پاسخ دهید
    (A)
    Uridine
  • 12
    Which nucleotide is most prevalent in a free state within animal cells?
    پاسخ دهید
    (A)
    ATP
  • 13
    Approximately what is the average intracellular concentration of ATP in a mammalian cell?
    پاسخ دهید
    (A)
    1 mM
  • 14
    Which base is present in messenger RNA but absent in deoxyribonucleic acid?
    پاسخ دهید
    (D)
    Uracil
  • 15
    What is the function of 'Caps' in an RNA molecule?
    پاسخ دهید
    (B)
    Are unique to eukaryotic mRNA
  • 16
    How does prokaryotic mRNA differ from eukaryotic mRNA?
    پاسخ دهید
    (A)
    Can be polycistronic
  • 17
    What is the approximate size range of small stable RNA molecules?
    پاسخ دهید
    (C)
    90-300 nucleotides
  • 18
    What is the approximate range of small stable RNAs found within a single cell?
    پاسخ دهید
    (C)
    1,00,000-10,00,000
  • 19
    What is the approximate molecular weight of heterogenous nuclear RNA (hnRNA)?
    پاسخ دهید
    (A)
    More than 107
  • 20
    In RNA, why isn't the guanine content always equal to cytosine, and adenine always equal to uracil?
    پاسخ دهید
    (A)
    Single strand molecule
  • 21
    Which nitrogenous base is found in RNA?
    پاسخ دهید
    (B)
    Uracil
  • 22
    Which of the following is NOT a component of RNA?
    پاسخ دهید
    (C)
    Thymine
  • 23
    What type of sugar is found in RNA?
    پاسخ دهید
    (C)
    Ribose
  • 24
    Which statement accurately describes base pairing in an RNA molecule?
    پاسخ دهید
    (D)
    Guanine content does not necessarily equal its cytosine content.
  • 25
    In which type of RNA are methylated purines and pyrimidines typically found?
    پاسخ دهید
    (C)
    tRNA
  • 26
    Where is Thymine typically found?
    پاسخ دهید
    (A)
    tRNA
  • 27
    What is the approximate number of nucleotides in a tRNA molecule?
    پاسخ دهید
    (C)
    75
  • 28
    In a typical cell, what is the minimum number of different tRNA molecules present?
    پاسخ دهید
    (B)
    20
  • 29
    What shape does a tRNA molecule resemble?
    پاسخ دهید
    (C)
    Clover leaf
  • 30
    In tRNA molecules, the CCA sequence is always located at the:
    پاسخ دهید
    (A)
    3' Termini
  • 31
    What is the basis for classifying Transfer RNAs?
    پاسخ دهید
    (D)
    Extra arm
  • 32
    Which modified base is found in the D arm of a tRNA molecule, giving it its name?
    پاسخ دهید
    (A)
    Uridine
  • 33
    How many base pairs are typically found in the acceptor arm of a tRNA molecule?
    پاسخ دهید
    (B)
    7 Base pairs
  • 34
    How many base pairs does the anticodon arm of a tRNA molecule typically possess?
    پاسخ دهید
    (A)
    5 Base pairs
  • 35
    What sequence is typically found in the TΨC arm of a tRNA molecule?
    پاسخ دهید
    (A)
    T, pseudouridine and C
  • 36
    Who put forth the double helical structure model of DNA?
    پاسخ دهید
    (C)
    Watson and Crick
  • 37
    Which of the following is NOT found in DNA?
    پاسخ دهید
    (C)
    Uracil
  • 38
    What is the type of sugar molecule found in DNA?
    پاسخ دهید
    (A)
    Deoxyribose
  • 39
    DNA segments with a high concentration of A-T pairs are stabilized by how many hydrogen bonds?
    پاسخ دهید
    (B)
    2 Hydrogen bonds
  • 40
    Which statement accurately describes the base composition in a DNA molecule?
    پاسخ دهید
    (D)
    Guanine content equals cytosine content
  • 41
    DNA with a high proportion of G-C pairs tend to have what characteristic regarding hydrogen bonds?
    پاسخ دهید
    (C)
    3 Hydrogen bonds
  • 42
    Given that DNA carries an organism's genetic code, what can be logically inferred about its base composition across different tissues?
    پاسخ دهید
    (C)
    DNA from different tissues in the same organism should usually have the same base composition
  • 43
    What is the approximate width of the B-form DNA double helix in nanometers?
    پاسخ دهید
    (B)
    2
  • 44
    How many base pairs are typically found in a single complete turn of the B-form DNA molecule?
    پاسخ دهید
    (C)
    10
  • 45
    What is the distance, in nanometers, covered by one full turn of B-form DNA?
    پاسخ دهید
    (D)
    3.4 nm
  • 46
    If the thymine concentration in a DNA molecule is 30%, what is the predicted concentration of guanosine?
    پاسخ دهید
    (B)
    20%
  • 47
    If the guanosine content in a DNA molecule is 40%, what would be the percentage of adenine?
    پاسخ دهید
    (A)
    10%
  • 48
    What factor leads to a higher melting temperature in duplex DNA?
    پاسخ دهید
    (C)
    Cytosine + Guanine
  • 49
    What condition is often treated with the synthetic nucleotide analogue, 4-hydroxypyrazolopyrimidine?
    پاسخ دهید
    (B)
    Gout
  • 50
    Which synthetic nucleotide analogue is frequently used in cancer and viral infection treatment?
    پاسخ دهید
    (A)
    Arabinosyl cytosine