Quick Biochemistry - Nucleic Acids (Section 1)

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