大学MOOC Medical Biochemistry(Shandong University)1458047170 最新慕课完整章节测试答案

Quiz

1、多选题：
‌The correct descriptions about hemoglobin(Hb) are‏
选项：
A: Oxygen dissociation curve is a rectangular hyperbola (a simple hyperbolic curve).
B: The four subunits have the same equilibrium constant with O2.
C: Binding with O2 has a positive cooperativity.
D: The conformation is in T state without O2.
答案: 【 Binding with O2 has a positive cooperativity.;
The conformation is in T state without O2.】

Unit test

1、单选题：
‌The chemical bond between the A and B chains of insulin is‌
选项：
A: peptide bond
B: disulfide bond
C: phosphoester bond
D: ionic bond
E: hydrophobic force
答案: 【 disulfide bond】

2、单选题：
‍The characteristic of secondary structure in myoglobin is to have more‍
选项：
A: α-helix
B: β-pleated sheet
C: β-strand 
D: loop
E: βαβ motif
答案: 【 α-helix】

3、单选题：
‍Autoclave disinfection is to make bacterial proteins‏
选项：
A: denaturation
B: precipitation
C: ionization
D: dissolved
E: degradation
答案: 【 denaturation】

4、单选题：
‏The protein whose structural change can cause sickle cell anemia is‌
选项：
A: lactate dehydrogenase
B: pyruvate kinase
C: insulin
D: myoglobin
E: hemoglobin
答案: 【 hemoglobin】

5、单选题：
‏The amino acid that can form disulfide bond in protein structure is​
选项：
A: Trp
B: Met
C: Cys
D: Pro
E: Ser
答案: 【 Cys】

6、单选题：
‌Protein denaturation is due to‏
选项：
A: conformation destruction of protein
B: depolymerization of protein subunits
C: proteolysis
D: changes in the primary structure of protein
E: breaking of peptide bonds
答案: 【 conformation destruction of protein】

7、单选题：
‏The amino acid without the asymmetric carbon atom is‎
选项：
A: Tyrosine
B: Serine
C: Glycine
D: Glutamate
E: Leucine
答案: 【 Glycine】

8、单选题：
‏At the isoelectric point, the protein behaves as‌
选项：
A: The molecular net charge is zero
B: The molecule most charged
C: Not easy to be precipitated
D: Increased solubility
E: Directional movement under the electrophoresis
答案: 【 The molecular net charge is zero】

9、单选题：
‏Which of the following amino acids is imino acid？‌
选项：
A: proline
B: histidine
C: glycine
D: tryptophan
E: lysine
答案: 【 proline】

10、单选题：
‌Which of the following amino acids does not exist in protein molecule‌
选项：
A: cysteine
B: histidine
C: citrulline
D: arginine
E: lysine
答案: 【 citrulline】

11、单选题：
‌Which of the following chemical bonds is involved in maintaining α-helix and β- pleated sheet？‎
选项：
A: peptide bond
B: ionic bond/salt bond
C: disulfide bond
D: hydrophobic effect
E: hydrogen bond
答案: 【 hydrogen bond】

12、单选题：
‏A solution contains the mixture of four kinds of protein, A, B, C and D, whose pI  are 6.0, 2.77, 9.74 and 5.07, respectively. The electrophoresis method is carried out to separate these four proteins in the electric field with pH=9.0 buffer. The sequence of the electrophoresis zone from the positive pole to the negative pole is as follows‎
选项：
A: A-B-C-D
B: B-D-A-C
C: B-D-C-A
D: D-B-A-C
E: B-A-D-C
答案: 【 B-D-A-C】

13、多选题：
‏Secondary structures of protein mainly include​
选项：
A: α helix
B: β conformation
C: β turn
D: motif
E: random coil
答案: 【 α helix;
β conformation;
β turn;
random coil】

14、多选题：
‌Which of the following descriptions about tertiary structure of protein are correct?‌
选项：
A: All polypeptide chains with tertiary structure have biological activities.
B: Most hydrophilic groups are located on the surface of tertiary structure.
C: The stability of tertiary structure is maintained by covalent bonds.
D: Tertiary structure is three-dimensional arrangement of all atoms in a polypeptide chain.
E: Formation of tertiary structure is the result of interaction between side chain groups of a polypeptide chain.
答案: 【 Most hydrophilic groups are located on the surface of tertiary structure.;
Tertiary structure is three-dimensional arrangement of all atoms in a polypeptide chain.;
Formation of tertiary structure is the result of interaction between side chain groups of a polypeptide chain.】

15、多选题：
‌Compared with myoglobin, hemoglobin is characterized by‌
选项：
A: Having quaternary structure
B: Containing heme
C: Having cooperative effects between subunits during combination with oxygen
D: The oxygen dissociation curve is S-shaped.
E: The main function is to transport oxygen.
答案: 【 Having quaternary structure;
Having cooperative effects between subunits during combination with oxygen;
The oxygen dissociation curve is S-shaped.;
The main function is to transport oxygen.】

16、多选题：
​The UV absorption properties of protein are due to the presence of​
选项：
A: tryptophan
B: glutamic acid
C: tyrosine
D: aspartic acid
E: histidine
答案: 【 tryptophan;
tyrosine】

17、多选题：
‏Which of the following amino acids contain hydroxyl group?‍
选项：
A: serine
B: phenylalanine
C: tyrosine
D: threonine
E: methionine
答案: 【 serine;
tyrosine;
threonine】

18、多选题：
​Which of the following descriptions about peptide unit are correct‏
选项：
A: Peptide unit is the basic unit forming the secondary structure of a polypeptide chain.
B: The six atoms that form peptide bond are in the same plane.
C: The bond length of peptide bond is between the length of single bond and double bond.
D: The single bond that connects to α-carbon atom can rotate freely.
E: The rotation angle between neighbor peptide units is affected by the side chains.
答案: 【 Peptide unit is the basic unit forming the secondary structure of a polypeptide chain.;
The six atoms that form peptide bond are in the same plane.;
The bond length of peptide bond is between the length of single bond and double bond.;
The single bond that connects to α-carbon atom can rotate freely.;
The rotation angle between neighbor peptide units is affected by the side chains.】

19、判断题：
‌When the pH > pI of protein, the proteins have positive charge.‎
选项：
A: 正确
B: 错误
答案: 【 错误】

20、判断题：
‍Glutathione acts as an antioxidant through its thiol group (-SH) in the molecule.‍
选项：
A: 正确
B: 错误
答案: 【 正确】

21、判断题：
‍Only those peptides with larger molecular weight containing 10 or more amino acids have biological activities.‌
选项：
A: 正确
B: 错误
答案: 【 错误】

22、判断题：
​Each subunit in the quaternary structure of a protein can exert its function independently.‏
选项：
A: 正确
B: 错误
答案: 【 错误】

Quiz

1、单选题：
​What kind of bond is broken in zymogen activation?​
选项：
A: hydrogen bond
B: ionic bond
C: peptide bond
D: hydrophobic bond
答案: 【 peptide bond】

Unit test

1、单选题：
‌Which of the following statements about active center of enzyme is not true?‎
选项：
A: Binding of enzyme with substrate is limited to the small area of enzyme structure which is closely related to enzyme activity.
B: The essential groups may locate either in or outside the active center.
C: Usually consists of several amino acid residues adjacent to each other in the primary structure
D: Zymogen activation is actually the process of forming complete active center.
E: Binding of substrates can induce conformational change of the active center of enzyme.
答案: 【 Usually consists of several amino acid residues adjacent to each other in the primary structure】

2、单选题：
‎When [S]=2Km, the velocity of an enzyme catalyzed reaction equals to‌
选项：
A: Vmax
B: 2/3Vmax
C: 3/2Vmax
D: 2Vmax
E: 1/2Vmax
答案: 【 2/3Vmax】

3、单选题：
‌The effect of temperature on the rate of enzymatic reaction is‍
选项：
A: When the temperature rises, the reaction rate increases, which is exactly the same as that of ordinary catalysts.
B: Low temperature may denature the most enzymes.
C: The optimum temperature is the characteristic constant of enzyme and is not related to the reaction time.
D: The optimum temperature is not the characteristic constant of enzyme. The longer the reaction time, the lower the optimum temperature.
E: All enzymes have the same optimum temperature.
答案: 【 The optimum temperature is not the characteristic constant of enzyme. The longer the reaction time, the lower the optimum temperature.】

4、单选题：
‎The inhibitory effect of organophosphorus insecticide on cholinesterase belongs to‌
选项：
A: Reversible inhibition
B: Competitive inhibition
C: Noncompetitive inhibition
D: Uncompetitive inhibition
E: Irreversible inhibition
答案: 【 Irreversible inhibition】

5、单选题：
‎Which of the following is the reversible inhibitor?​
选项：
A: organophosphorous compound
B: organic mercury compound
C: organoarsenic compound
D: cyanide
E: sulfonamides
答案: 【 sulfonamides】

6、单选题：
‍Competitive reversible inhibitors of enzyme can make‌
选项：
A: Vmax decreases, Km decreases
B: Vmax increases, Km increases
C: Vmax remains unchange, Km increases
D: Vmax remains unchange, Km decreases
E: Vmax decreases, Km increases
答案: 【 Vmax remains unchange, Km increases】

7、单选题：
‏About the statements on allosteric enzyme and allosteric regulation, the correct is‎
选项：
A: All allosteric enzymes have a regulatory subunit and a catalytic subunit.
B: The kinetic characteristics of allosteric enzyme are S-shaped curve rather than rectangular hyperbola.
C: The mechanism of allosteric activation is the same as that of enzyme activator.
D: Sulfonamides work by allosteric inhibition.
E: It is an important way to rapidly regulate the enzyme content.
答案: 【 The kinetic characteristics of allosteric enzyme are S-shaped curve rather than rectangular hyperbola.】

8、单选题：
‏The most common covalent modification of enzyme is‍
选项：
A: Phosphorylation/Dephosphorylation
B: Adenylation/Deadenylation
C: Methylation/Demethylation
D: Acetylation/Deacetylation
E: -SH / -S-S-
答案: 【 Phosphorylation/Dephosphorylation】

9、单选题：
‍Which of the following inhibition can be reduced by increasing [S]?‎
选项：
A: Irreversible inhibition
B: Competitive inhibition
C: Noncompetitive inhibition
D: Uncompetitive inhibition
E: Unable to determine
答案: 【 Competitive inhibition】

10、单选题：
‏Which of the following statements about enzyme is false?‍
选项：
A: All proteins are enzymes.
B: Enzymes are biocatalysts.
C: Enzymes are synthesized inside cells, but can perform catalytic functions outside cells.
D: Enzymes have high specificity.
E: Enzymes can be inactivated by certain denaturing factors.
答案: 【 All proteins are enzymes.】

11、单选题：
‎The region in an enzyme to which a substrate binds is called the‏
选项：
A: center area
B: docking station
C: peptide fold
D: active site
E: binding site
答案: 【 active site】

12、单选题：
​A competitive inhibitor of an enzyme is usually‌
选项：
A: a highly reactive compound
B: structurally similar to the substrate
C: water insoluble
D: a poison
E: an enzyme analogue
答案: 【 structurally similar to the substrate】

13、单选题：
‌The allosteric effector of an enzyme usually‏
选项：
A: binds to the active site
B: changes the conformation of the enzyme
C: denatures the enzyme
D: causes the enzyme to work faster
E: inhibits the enzyme activity
答案: 【 changes the conformation of the enzyme】

14、多选题：
‍Enzymes have the following characteristics compared with common catalysts‏
选项：
A: high catalytic efficiency
B: high specificity for substrates
C: can lower the activation energy of reactions
D: can't change the equilibrium of reactions
E: enzyme activity can be regulated
答案: 【 high catalytic efficiency;
high specificity for substrates;
enzyme activity can be regulated】

15、多选题：
‎Which of the following amino acid residues in enzyme molecule can be modified by phosphorylation?​
选项：
A: Tyr
B: Cys
C: Ser
D: Gly
E: Thr
答案: 【 Tyr;
Ser;
Thr】

16、判断题：
​Km is the characteristic constant of enzyme, which is only related to the properties of enzyme and is not related to the concentration of enzyme.‎
选项：
A: 正确
B: 错误
答案: 【