依璇 asked in 科學生物學 · 8 years ago

生物化學題目1 懇請解答

1) Which of the following bases is found only in DNA?

A) adenine

B) thymine

C) uracil

D) cytosine

E) guanine

2) Which of the following is correctly paired?

A) adenine: pyrimidine

B) RNA: ribose containing nucleic acid

C) thymine: purine

D) uracil: purine

E) DNA: ribose containing nucleic acid

3) Which of the following correctly describes the structure of a nucleotide?

A) adenine is bound via a link between N-7 and C-1 of ribose

B) phosphates are always bound to C-2 of ribose

C) cytosine is bound via a link between the amine on C-4 and C-1 of ribose

D) guanine is bound via a link between N-9 and C-1 of ribose

E) none of the above

4) Which of the following is correctly paired with the type of tautomerization(s) that occurs?

A) adenine: keto-enol

B) cytosine: amino-imino and keto-enol

C) guanine: amino-imino

D) thymine: keto-enol

E) none of the above

5) Based on the following, what can be said about the synthesis of polynucleotides?

A) polynucleotides are unstable and are rapidly degraded

B) polynucleotide formation is made much more exergonic by the hydrolysis of pyrophosphate

C) the hydrolysis of nucleoside triphosphates is the only driving force to make an overall irreversible reaction

D) polynucleotides are highly resistant to hydrolysis, even in the presence of an acid catalyst

E) none of the above

6) Which of the following describes the directionality seen in nucleic acids?

A) most polynucleotides have an unreacted 5 hydroxyl group

B) all polynucleotides have an unreacted 2 hydroxyl group

C) most polynucleotides have a phosphate group on the 5 end

D) sequences of polynucleotides are generally written from 3 on the left to 5 on the right

E) none of the above

1 Answer

Rating
  • 8 years ago
    Favorite Answer

    B

    B

    D

    D

    B

    C

    哈哈跟我們的題庫一模一樣呢

    Source(s): 老師給的解答
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