大学MOOC Medical Molecular Biology(Shandong University)1461332169 最新慕课完整章节测试答案

The structure and function of nucleic acid

1、单选题：
​ ‍Which of the following are pyrimidines? ‍
选项：
A:  adenine and cytosine
B: adenine and guanine 
C: adenine and thymine
D:  cytosine and thymine
E: guanine and thymine
答案: 【  cytosine and thymine】

2、单选题：
​ ‌Which kind of nucleotide does not exist in DNA？‌
选项：
A: dAMP
B: dTMP
C: dUMP
D: dGMP
E: dCMP
答案: 【 dUMP 】

3、单选题：
‌ ‏Which of the following is the
connection of primary structure of nucleic acid molecule? ‏
选项：
A: 2 ′, 3 ′ phosphodiester bond
B: 3 ′, 5 ′ phosphodiester bond
C:  2 ′, 5 ′ phosphodiester bond  
D:  glycosidic bond
E: hydrogen bond
答案: 【 3 ′, 5 ′ phosphodiester bond】

4、单选题：
‏ ‍In
nucleotide molecule, which carbon atom of ribose and the purine N9
linked by glycosidic bond? ‍
选项：
A: C-1 '
B: C-2 '
C: C-3 '
D: C-4 '
E: C-5 '
答案: 【 C-1 '】

5、单选题：
​ Which
of the following may be right if a nucleic acid has the following base composition: A
= 16%, G= 39%, C = 22%, T= 23% (C)? ‎
选项：
A: double strand DNA
B:  tRNA
C: single strand DNA
D: single strand RNA
E: double strand RNA
答案: 【 single strand DNA】

6、单选题：
‍Which of the following refers to melting temperature of DNA?‏
选项：
A:  The
temperature when A260 reached the
maximum
B: The temperature when A260 reaches
the maximum value of 50%
C:  DNA
begin unwinding of temperature
D: The complete unwinding DNA
strands of the temperature
E: The temperature when A280 reaches
the maximum value of 50%
答案: 【 The temperature when A260 reaches
the maximum value of 50% 】

7、单选题：
‌ In nucleic acid molecules, which of the following is the key part that the genetic information is stored in? ‏
选项：
A: pentose conformation
B: The rotation angle of bases
C:  The base sequence
D: pentose phosphate backbone
E: phosphate ester bond
答案: 【  The base sequence】

8、多选题：
‌Which are correct about the descriptions of nucleic acid
molecular hybridization?‍
选项：
A: It refers to renaturation of denatured DNA
B: DNA can be
hybridized with RNA to form a double helix 
C: RNA can be
hybridized with its encoded polypeptide chain 
D:  It can detect the homology
between hybrid nucleic acids
E:  ‍DNA or RNA
from different sources can be hybridized as long as some bases can pair 
答案: 【 DNA can be
hybridized with RNA to form a double helix ;
 It can detect the homology
between hybrid nucleic acids;
 ‍DNA or RNA
from different sources can be hybridized as long as some bases can pair 】

9、多选题：
​Which are correct about the descriptions of mRNA?‎
选项：
A: Among the three RNAs, the metabolic rate is the fastest‍
B: The
secondary structure contains local double helix
C:  It consists of
two subunits
D: There are m7Gppp cap
and polyA tail
E: It contains genetic information
答案: 【 Among the three RNAs, the metabolic rate is the fastest‍;
The
secondary structure contains local double helix;
There are m7Gppp cap
and polyA tail;
It contains genetic information】

10、多选题：
‍The sequence of a DNA strand is 5 '- A-T-T-C-3', which
can be its complementary strand?​
选项：
A: 5′-T-A-A-G-3′
B: 5′-T-C-C-G-3′
C: 5′-G-A-A-T-3′
D: 5′-U-A-A-G-3′
E: 5′-G-A-A-U-3′
答案: 【 5′-G-A-A-T-3′;
5′-G-A-A-U-3′】

DNA replication

1、单选题：
‌​Which
statement is correct about DNA pol in prokaryotes​‌​
选项：
A: DNA-pol I
is the major DNA replicase
B: DNA-pol II has highest activity, is the major enzyme in DNA replication
C:  DNA-pol III is the major DNA replicase, and has the 3′→5′ exonuclease activity
D:  DNA-pol III seal the nick during replication and repair
E: DNA-pol II has 5′→3′ exonuclease activity
答案: 【  DNA-pol III is the major DNA replicase, and has the 3′→5′ exonuclease activity】

2、单选题：
‎‌The
function of DNA topoisomerase is‌‎‌
选项：
A: to stable
unwound DNA duplex
B: to recognize replication origin site
C:  to synthesize RNA primer
D:  to unwind DNA duplex, in order to replicate
E: to unwind DNA super coil, avoid tangling together
答案: 【 to unwind DNA super coil, avoid tangling together】

3、单选题：
​​Which
process doesn’t require DNA ligase​​​
选项：
A: DNA damage repairing
B: reverse transcription
C: DNA replication
D: DNA recombination
E: genetic engineering
答案: 【 reverse transcription】

4、单选题：
‌​The
function of RNA primer is ​‌​
选项：
A: to separate DNA double helix
B: to provide 3′-OH to synthesize DNA molecule
C: to provide 5′-P to synthesize DNA molecule
D: to provide 5′-P to synthesize RNA molecule
E: to release supercoil of  DNA
答案: 【 to provide 3′-OH to synthesize DNA molecule】

5、单选题：
‌‏Which
enzyme can use RNA as template to synthesize DNA molecule‏‌‏‏‌‏
选项：
A: RNA pol
B:  reverse transcriptase
C: DNA topoisomerase
D: DNA helicase
E: DNA ligase
答案: 【  reverse transcriptase】

6、单选题：
‌‏About
DNA replication origin site, which one is correct‏‌‏‌‏
选项：
A: has one origin site only in prokaryotes
B: has multi-origin site in prokaryotes
C: has one origin site in eukaryotes
D: recognize and bind by β subunit of DNA-pol III
E:  recognize and bind by primase
答案: 【 has one origin site only in prokaryotes】

7、单选题：
‍‏Which
statement about DNA replication is WRONE‏‏‍‏
选项：
A: require primer
B: is bidirectional replication
C: is semiconservative replication
D: is semidiscontinuous replication
E: the orientation of newly synthesized chain is 3’→5’
答案: 【 the orientation of newly synthesized chain is 3’→5’】

8、多选题：
‏‎The
biological activity of prokaryotic DNA pol III involve:‎‏‎‎‏‎
选项：
A: 5′→3′ exonuclease activity
B: 5′→3′ polymerization activity
C: 3′→5′ exonuclease act