中南大学生物化学考试试卷
2005--2006学年 二
学期 时间110分钟
Part I Filling Blankets (0.5 point
each, 25 pts)
Please fill each blanket with suitable word(s) either in English
or Chinese
1.
Glycolysis provides the organism
( ) as well
as energy.
2.
The two typical photosystems PSI and PSII for plant cells or
cyanobacteria (蓝细菌) are
( ) and
( ), where the original
electron donor is
( ) and the
final electron acceptor is ( ).
Besides ATP, the other substance produced by the photosystems is
( ).
3.
The two basic amino acids are (
) and ( ), the two acidic amino
acids are ( ) and
( ), and the three aromatic
(芳香)amino acids are ( ),
( ) and
( ).
4.
The two epimers (异头体)of glucose in pyrano-forms are
( ) and
( ).
5.
The typical storage lipids are named
( ), the
typical membrane lipids are
( ).
6.
For a typical membrane, when dipalmitoyl phosphtidylcholine
(二棕榈酸磷脂酰胆碱)increases in the membrane, Tm value of the
membrane will
( ).
7.
Melting temperature of DNA may
( ) with increase in
electrolyte concentration or GC content.
8.
The two major products of pentose phosphate pathway are
( ) and
( ).
9.
Proline can occur in the ( ) of
an a-helix of polypeptide.
10. The two standard amino acids that have not chairal (手性)
carbon atoms are ( ) and
( ).
11. The membrane proteins can be classified into three types,
they are ( ),
( ) and
( ).
12. The amino acids that link to the sugar units either by O- or
N-linkage in proteoglycans (蛋白多糖)or glycoproteins (糖蛋白), typically
include ( ),
( ), and
( ).
13. a-keratins have a-helix, b-keratins have
( ).
14. The typical five sugars repeat unit in the core structure of
oligosaccharides (寡聚糖) in N-linked glycoproteins include two
molecules of ( ) and three
molecules of ( ).
15. In the reversible competitive inhibition, the
inhibitor binds to the ( ) site
of the enzyme, and in the reversible noncompetitive inhibition, the
inhibitor binds to the ( ) site
of the enzyme. Both these two inhibitions are by way of
( ) binding.
16. The two mobile electron carriers in the
electron transport chain are (
) and ( ).
17. In the K-type of inhibition, the
apparent Km will
( ), though the
Vmax keeps unchanged.
18. The anticodon of AUG is ( ).
19. The general procedure for the transformation of
atmosphere N2 into organic substance is (1)
( ), (2) assimilation of
NH3 into amino acids, and (3) biotransfer of amino acids
(normally beginning with glutamate) into other organic
substance.
20. The Calvin cycle is responsible for the
fixation of ( ).
21. DNA is always synthesized in the
( )
direction.
22. In a typical cycle of b-degradation of C16 saturated fatty
acids, it includes two steps of oxidation, in which the electron
carriers or cofactors are respectively
( ) and
( ).
23. Carboxylation (羧化)enzymes often require the prosthetic group
(辅基) ( ).
24. Transamination (转氨作用) with tansaminase needs an prosthetic
group ( ).
25. The most representative molecules with high energy include
( ), and
( ),besides the NTPs.
26. The common substance entering into TCA cycle for b-oxidation
of fatty acids and glycolysis is
( ).
Part II Structural details for some typical
biomolecules (15 pts)
1.
If a physiological phosphatidylcholine (磷脂酰胆碱)consists of palmitic
and linoleinic acids(棕榈酸和亚麻酸), please write the physiologically
correct structure, if you take P and L as palmitic and linoleinic
acids, respectively. (2分)
2.
Please give the name for the following oligosaccharide (寡糖),in
which you should give the glycolinkage forms, steric configuration
(构型) as well as the names of the monosaccharide residues
(单糖残基).(3分)
3.
Please complete the following reaction by adding the fitful
reactant(s), product(s), enzyme and cofactor on the suitable side
of the equation. Known that this reaction is the oxidation step of
glycolysis (糖酵解). (3分)
4.
Please give the nucleotide sequence of the DNA template strand from
which the following mRNA segment was transcribed:
5’-UAGUGACAGUUGCGAU-3’. (2分)
5.
Please write the open reading frame for mRNA of typical prokaryotic
cells. (2分)
6.
Please write the typical structure of Lac operon (乳糖操纵子).
(3分)
Part III Short essay questions (30
pts)
Please concisely answer the following short essay
questions in English or Chinese.
1.
What is the key enzyme included in the Calvin cycle, and how does
it respond to the light imposed on the photosynthetic organelles ?
(3分)
2.
Please compare the differences in characteristics between passive
transport and active transport. (4分)
3.
What are the differences in physiological functions between NADH
and NADPH? (4分)
4.
What are major fates of the final product of glycolysis? (3分)
5.
An oligopeptide (寡肽) with a sequence of
NH3+-SIKDYEFRMP-COO-, please point
out the sequence of the peptide in amino acids names. (5分)
6.
What are the typical types of the secondary structures of proteins,
and what force(s) for the secondary structures of proteins?
(5分)
7.
Determine the number of ATP equivalents needed to form palmitic
acid from acetyl-CoA. (Assume for this calculation that each NADPH
is worth 3.5ATP.)? (3分)(you should describe the reason for that
determination)
8.
What are the fates for oxaloacete (or what pathways require
oxaloacetate 草酰乙酸)? (4分)(you should describe the relationship
between some pathways that require or are related to
oxaloacetate)
Part IV Complex essays ( 15 pts)
1. Please answer the following questions according to the figure
below (10分).
(1) This pathway is TCA
cycle, What does TCA mean ? (1分)
(2) What are the entry and
exit substance, respectively, for this pathway. (1分)
(3) What specific enzymes
are used for steps 2 and 3, respectively? (1分)
(4) Why citrate needs to be
transferred into isocitrate before it is oxidized ? (1分)
(5) In step 6, why the
cofactor FAD is used as the electron acceptor. (1分)
(6) What are the major
control steps? (1分)
(7) How do the high
concentrations of ATP and NADH regulate the pathway, why ? (1分)
(8) Explain the important
role for this pathway. (1分)
(9) How many ATPs can be
formed from one molecule of pyruvate by way of TCA cycle and
oxidative phosphorylation. (2分)
2. Please explain the mechanism of covalent modification and
allosteric regulation of glycogen phosphorylase (糖原磷酸水解酶)according
to the figure below, in which the phosphorylase a is more
active than the phosphorylase b . (5分)
Part V Calculations and Sequence Analysis
(15 pts)
1.
For a Michaelis-Menten reaction,
k1=7×107(mol/L sec),
k-1=1×103(sec), and
k2=2×104(sec). What is the value of
Km? Does substrate binding approach equilibrium
or does it behave more like a steady-state system? If
Vmax=100 mmol/mL sec, what is the velocity of the
reaction when [S]=20mmol/L ? (6分)
2.
Amino acid analysis of an oligopeptide seven residues long gave
Asp, Leu, Lys, Met, Phe, Tyr. The following facts were
observed:
a.
Trypsin (胰蛋白酶) treatment had no apparent effect.
b.
The phenylthiohydantoin (苯基硫代乙内酰脲)released by Edman degradation
was
c.
Brief chymotrypsin (胰凝乳蛋白酶)treatment yielded several products,
including a dipeptide (双肽) and a tetrapeptide (四肽). The amino acid
composition of the tetrapeptide was Leu, Lys, and Met.
d.
Cyanogen bromide (溴化氰)treatment yielded a dipeptide, a
tetrapeptide, and free Lys.
What is the amino acid sequence of this heptapeptide (七肽)?)?
(9分)
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