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1
The rules of the contest
•There are 6 groups,3 groups from
each sections and each group
includes 3 students ;
•There are single choose questions ，
rushing to answer questions(true or
false and fill in the blank)，
short /long answer questions and
audient answer questions.
•Short and long answer questions
will scored by the judges .
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The first round
single choose questions
The rules of the round
There are 5 choices(A,B,C,D,E),among
them only one answer is correct. each
students from each group must be answer
one question, if correct 50marks will be
added, if wrong discount any marks。
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Choose below please
Table
tennis
banana
cake
math
lemon
tomato
physics
Badminton
Water
melon
Mahmud
tea
biology
Baseball
apple
juice
surgeon
Football
orange
milk
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ok
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• 1 Eukaryotic cells usually contain
•A. a nucleus.
•B. mitochondria.
•C. ribosomes.
•D. microtubules.
•E. all of the above.
Answer：E
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7
• 2 The bonds that join the
nucleotides to form a single strand
of DNA are
•A. peptide bonds.
•B. hydrogen bonds.
•C. phosphodiester links.
•D. van der Waals bonds.
•E. disulfide bonds.
Answer:C
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• 3 Peptide bonds are
formed by:
•A reduction;
•B oxidation;
•C hydration;
•D condensation reaction;
•E none of the above.
Answer：D
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back
•4· Ion channel proteins typically show
which of the following characteristics?
•A. lower transport rates than pumps
•B. movement of molecules up the
concentration gradient
•C. active transport
•D. energy is required
•E. passive transport
Answer：E
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• 5· The total ATP which
are produced in a complete
lysis of one glucose are:
•A. 3
B. 10
C. 30
•D. 35
E. 36
Answer：E
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• 6 The Na+/K+ ATPase functions
to:
•A. Move 3K+ ions out of the cell
and 2Na+ ions into the cell
•B. Move 2K+ ions out of the cell and
3Na+ ions into the cell
•C. Move 2Na+ ions out of the cell
and 3K+ ions into the cell
•D. Move 3Na+ ions out of the cell
and 2K+ ions into the cell
•E. Move 3Na+ ions and 2K+ ions out
of the cell
Answer：D
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13
14
back
• 7 Membrane carrier proteins differ from membrane
channel proteins by which of the following
characteristics?
•A. Carrier proteins are glycoproteins, while channel
proteins are lipoproteins.
•B. Carrier proteins transport molecules down their
electrochemical gradient, while channel proteins
transport molecules against their electrochemical
gradient.
•C. Carrier proteins can mediate active transport,
while channel proteins cannot.
•D. Carrier proteins do not bind to the material
transported, while channel proteins do.
•E. Carrier proteins are synthesized on free
cytoplasmic ribosomes, while channel proteins are
synthesized on ribosomes bound to the endoplasmic
reticulum.
Answer：C
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• 7 Membrane carrier proteins differ from membrane
channel proteins by which of the following
characteristics?
•A. Carrier proteins are glycoproteins, while channel
proteins are lipoproteins.
•B. Carrier proteins transport molecules down their
electrochemical gradient, while channel proteins
transport molecules against their electrochemical
gradient.
•C. Carrier proteins can mediate active transport,
while channel proteins cannot.
•D. Carrier proteins do not bind to the material
transported, while channel proteins do.
•E. Carrier proteins are synthesized on free
cytoplasmic ribosomes, while channel proteins are
synthesized on ribosomes bound to the endoplasmic
reticulum.
Answer：C
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Answer：E
• 8 The diverse group
of molecules that
comprises the lipids
may all be defined as
•A. being liquid at
room temperature
•B. having high melting
points
•C. hydrophilic
•D. water soluble
•E. fat soluble
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• 9 What causes the kink in
one of the phospholipids
fatty acid tails?
•A. the presences of
hydrogen atoms
•B. the presence of oxygen
atoms
•C. the absence of water
•D. the absence of oxygen
atoms
•E. a double bond
Answer：E
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19
back
• 10 What is usually the
Answer：A
major component of
plasma membranes of
Eukaryotes?
•A. Phospholipids
•B. Fats
•C. Cholesterol
•D. Nucleic acids
•E. Triglycerides
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20
• 11 All of the following describe
phospholipids EXCEPT
•A. they contain glycerol and two fatty acid
tails.
•B. they all contain a phosphate group.
•C. they are entirely hydrophobic.
D. in water, the tails tend to cluster
together.
•E. they are used in cell membranes.
Answer：C
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21
• 12 Which phospholipid carries a negative
charge?
•A. sphingolipids
•B. phosphatidylcholine
•C. phosphatidylserine
•D. phosphatidylethanolamine
•E. None of the above
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Answer：C
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back
13. Mitosis proceeds in the order to
A. cytokinesis, prophase, telophase,
metaphase, and anaphase.
B. telophase, anaphase, prophase, metaphase,
and cytokinesis.
C. prophase, metaphase, anaphase, telophase,
and cytokinesis.
D. prophase, metaphase, cytokinesis,
anaphase, and telophase.
E. prophase, cytokinesis, metaphase,
anaphase, and telophase.
Answer：C
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24
14. Which of the following statements about nucleoli is
true?
A. Nucleoli are membrane-bounded structures present
in the nucleus
B. A single nucleolus always corresponds to a single
nucleolar organizer region (NOR)
C. In animals, the disappearance of nucleoli during
mitosis is correlated with the cessation of ribosome
synthesis
D. The DNA of nucleoli encodes the cells tRNA genes
E. All of the above
Answer：D
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25
15.Actin filaments are
destabilized by:
A. phalloidin
B. actinomysin D
C. colcemid
D. cytochalasin
E. taxol
Answer：D
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back
16.O-linked glycosylation occurs on which
amino acids?
A.serine
B. asparagines C. tyrosine
D. threonine E. A and D
E
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17.Dyneins are motor proteins that:
A.cause movement of cilia and flagella
B. segregate chromosomes
C. move vesicles along microtubules
D. all of the above
E. A and B
D
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18.Taxol is thought to function as an anticancer drug because it:
A. directly inhibits the formation of microtubules, causing the
death of cancer cells that divide before essential microtubules
form.
B. directly inhibits the disassembly of microtubules, leaving
insufficient dimers for the synthesis of new microtubules.
C. causes deformation of microtubles.
D. causes premature disassembly of microtubules.
E. prevents the attachment of microtubules to chromosomes.
B
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30
The Second Round
The rules of contest：
Each group must be answer one
question，group members can discuss
in I minute，one of the contestant
answer question，each correct
question 100 marked ,if wrong no
discount.
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3
1
6
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5
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1 Describe the 3 Basic
tenets of the Cell Theory.
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Answer：
1. All organisms are composed of one
or more cells.
2.The cell is basic unit of structure and
function for all organisms.
3.All cells arise only from preexisting
cells by division.
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2 Who was first described the fluid-mosaic
model? What was its idea?
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Answer:
The Fluid Mosaic Model, proposed in 1972 by Singer and Nicolson,
had two key features, both implied in its name.
The core lipid bilayer exists in a fluid state, capable of dynamic
movement.
Membrane proteins form a mosaic of particles penetrating the lipid
to varying degrees.
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3 What is the difference between
active transport and facilitated
diffusion?
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Answer:
1) Active transport maintains the
gradients for potassium, sodium, calcium,
and other ions across the cell membrane.
Always moves solutes up a concentration
or electrochemical gradient;
2) Active transport always requires the
input of energy.
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4
Describe briefly the structure of
microtubule？
39
Answer:
(1)Hollow
(2)Tubular structures 25nm in
diameter
(3)Assembled
from
protein
tubulin
(4)The tubulin consists of alphabeta
tubulin
heterodimers
arranged in rows (protofilaments)
(5)Form cytoskeleton, mitotic
spindle, centrioles, core of cilia
and flagella.
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5 Describe briefly the difference
between euchromatin and
heterochromatin？
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Answer:
Euchromatin: Light-staining, less condensed; Transcriptional activity;
Located on the center of nucleus.
Heterochromatin:
Dark-staining,
condensed chromatin;
No transcriptional;
located on the interior suface of inner nuclear membrane.
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6 Describe briefly the functions of rough ER .
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Answer:
Functions of RER:
(1)Proteins synthesized on ribosomes of RER.
(2)Modification and processing of newly
synthesized proteins: glycosylation.
(3)Quality control of newly synthesized proteins.
(4)Synthesis of membrane lipids.
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7 Describe briefly the ultrastructure
and functions of Golgi complex.
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Answer:
The structure of Golgi complex:
Cis face and trans face;
Cis Golgi network(CGN),
cisterna(cis, medial, trans),
trans Golgi network(TGN).
The Functions of Golgi complex:
(1)Glycosylation.
(2)Protein sorting
(3)Cell secretion
(4)Biogenesis of Lysosomes.
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• The rules of the rushing to answer
questions ：
• one of the contestant answer question，
who presses button first!
• each correct question 50 marked ,
• if wrong 50 marks discount.
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1 The inner membrane of
mitochondria is folded into
.
Cristae
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True or false
•2.In the structure of DNA,
hydrophilic sugar–
phosphate backbones lie on
the inside of the molecule,
and the purines and
pyrimidines lie on the
outside of the molecule.
F
50
True or False
3.The process of endocytosis
does not require energy.
F
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•True or False
•4.Mitochondria is an
independent organelle.
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True or False
5.There are three major
classes of lipids:
phospholipids, glycolipids and
sterols (cholesterol).
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True or False
6.Channel proteins are
responsible for both the
passive and the active
transport. Carrier proteins
are only responsible for
passive transport.
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Fill in the blank
7.1000nm=
meter.
10 -6 m
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Fill in the blank
8.The core carbohydrate of N-linked
oligosaccharides is assembled in
. RER
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Fill in the blank
9.The inner surface of the nuclear
envelope is lined by
.
nuclear lamina
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Fill in the blank
10.Heterochromatin can be
divided into two classes:
constitutive and
.
facultative
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Fill in the blank
11 Most organelles in endomembrane
system are part of a
system in
which vesicles move between
compartments.
Dynamic
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Fill in the blank
12. ( ) are heterogeneous
mixtures of similar-sized
vesicles, formed from
membranes of the ER and Golgi
complex.
Microsomes
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•Audients answer questions
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1 Acetyl CoA formation occur
in matrix of mitochondria. It
produces one acetyl CoA and
one
(cofactor).
NADH
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•2 In the absence of specific
transport proteins, which of the
following diffuses most poorly
through a cell membrane?
•A. O2 gas
B. glucose
• C. H+
D. water
•E. glycerol
C
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•3 Which of the following is NOT
a property of the cell membrane?
•A. fluidity
•B. permeability to nonpolar
compounds
•C. permeability to water and
gases
•D. Rigidity
•E. impermeability to large polar
compounds
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4.How do cells take up the correct substrates
in endocytosis?
A. They don’t, they randomly take up
substrates and secrete what they don’t need.
B. The clathrin protein recognizes the correct
substrate and will concentrate it in vesicles.
C. The adaptin protein will recognize the
correct substrate and concentrate it in
vesicles.
D. A receptor, specific for the substrate, will
concentrate it into endocytic vesicles.
E. None of the above.
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5.The chromatins which are lightstaining, less condensed and
have transcriptional activity are
heterochromatin.
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6.Which of the following are
NOT components of the
cytoskeleton?
A.actin filaments
B. collagen fibers
C. microtubules
D. microfilaments
E. intermediate filaments
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7.What happens to the cargo receptors
once they have delivered its cargo?
A. They are degraded in the lysosome.
B. They are secreted from the cell.
C. They are recycled.
D. They remain in the cytosol.
E. None of the above.
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8.Which group of proteins are
motor proteins that interact with
microtubules?
A.tropomyosin
B. myosin
C. dynein
D. α-actinin
E. lamin
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The rules of the game：
Each participating team optional choose
different valued (200marks or 300marks)one
question and after discussions for one minute
in team, choose one participant to answer
the question.
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Choose me！
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1
4
5
6
7
2
3
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1 What
distinguishes the
two main types of
cells.
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返回
1ANSWER:
prokaryote
eukaryote
size
small
large
nucleus
absent
present
cell division
simple fission
inner
membrane
ribosome
rare
mitosis,
meiosis
complex
70S
80S
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What is the difference between
DNA and RNA?
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sugar
base
DNA
deoxyri A , G,
bose
C, T
RNA
ribose
strand
location
double
nucleus
A, G, C, single
U
cytopla
sm
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3List the four different
nucleotides found in
DNA, the typical WatsonCrick base pairings, and
the number of hydrogen
bonds in each of those
pairings.
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3 Ans: Four different nucleotide in DNA: dAMP,
dGMP, dCTP, dTTP.
Typical Waston-Crick base pairing: A pair with T,
form 2 hydrogen bonds; G pair with C, form 3
hydrogen bonds
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78
4Describe the main
opinions briefly about
Mithchell’s Chemiosmotic
theory.
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4 Ans: Mithchell’s Chemiosmotic theory:
(1).The electrochemical gradient resulting from
transport of protons links to oxidative
phosphorylation.
(2).When electrons are transported along the
chain, the H+ is translocated across the inner
membrane.
(3).The mitochondrial inner membrane is
impermeable to H+.
(4).When protons flow in the reverse direction
through the F1-F0 coupling factor complex, the
potential energy is released. It drives ATP
synthesis.
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5Describe briefly the
structure of microtubule？
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(1)Hollow
(2)Tubular structures 25nm in diameter
(3)Assembled from protein tubulin
(4)The tubulin consists of alpha-beta
tubulin heterodimers arranged in rows
(protofilaments)
(5)Form cytoskeleton, mitotic spindle,
centrioles, core of cilia and flagella.
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82
6 Describe briefly the
functions of Microfilaments.
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Functions of MFs:
(1)Maintain cell’s shape and enforce PM
(2) Cell migration
(3) Microvillus: Support the projecting
membrane of intestinal epithelial cells
(4) Contractile ring: For cytokinesis
(5) Muscle contraction.
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7Describe briefly the
functions of smooth ER.
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Functions of the SER:
(1)Synthesis of steroids in endocrine cells
(2)Detoxification of organic compounds in
liver cells
(3)Release of glucose 6-phosphate in liver
cells
(4)Sequestration of Ca2+
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1
4
5
6
7
2
3
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1 Describe the Chemical
Composition of plasma membrane in
detail.
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1.Ans: I.Membrane Lipid
1. Phospholipids : The major lipids, 50-90% of total lipid content. Most
phospholipids are derivatives of diacyl-glycerol-3-phosphate, phosphatide)
2. Cholesterol: 5-25% of membrane content, sterols are usually more concentrated
in the plasma membrane of an animal cell
3. Glycolipids: the least abundant, usually less than 5%
Ⅱ.Membrane Protein
1. Integrated (transmembrane) proteins: Penetrate the hydrophobic core of the lipid
bilayer, Are often transmembrane proteins, completely spanning the membrane.
2. Peripheral membrane proteins: Proteins on either side of the membrane that
associate with the polar ends of transmembrane proteins by noncovalent (ionic)
interaction. Are appendages loosely bound to the surface of the membrane
III.Membrane carbohydrate: Interact with the surface molecules of other cells,
facilitating cell-cell recognition. There are two existing ways, they are Glycoprotein,
Glycolipid.
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89
2 Describe briefly the process about
the receptor-mediated endocytosis of
low-density lipoprotein (LDL).
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2Answer:
The process of receptor-mediated
endocytosis include:
1) LDL bind to LDL receptor which
distribute on cell membrane.
2) Invagination on the cytosolic surface of
the cell membrane, form the coated vesicle.
3) Losing the coat, it become uncoated
vesicle.
4) Fusion with early lysosome, divided into
two vesicles.
5) LDL receptor recycling to the cell
membrane, LDL is digested by enzymes
exist in lysosome
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3Describe the transportation
functions of plasma membrane in
detail.
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3 Ans: There are 2 kinds of main categories of membrane transportation;
they are passive and active transport.
Passive one: Molecules move from areas of high concentration to areas of
low concentration without the aid of ATP energy. There are three types of
passive transportation: Diffusion, Facilitated Diffusion and Osmosis.
Diffusion is the way of Molecules can move directly through the
phospholipids of the plasma membrane. Diffusion is the net movement of
molecules from a high concentration to a low concentration until equally
distributed. Example:O2 moves in and CO2 moves out during cell
respiration.
Facilitated Diffusion: Molecules can move through the plasma membrane
with the aid of transport proteins (channel or carrier proteins).
Gated Channels – receptors combined with channel proteins. When a
chemical messenger binds to a receptor, a gate opens to allow ions to flow
through the channel. For example: glucose and amino acids enter cell for
cell respiration.
Osmosis: Water molecules can move directly through the phospholipids of
the plasma membrane. Osmosis is the diffusion of water through a
semipermeable membrane.
Active transport: Molecules move from areas of low concentration to areas
of high concentration with the aid of ATP energy.
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4 Explain the process of
biogenesis of lysosome via
mannose-6-phosphate pathway？
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(1)Precursors of lysosomal enzymes migrate from the rER to the cisGolgi where mannose residues are phosphorylated. (1 mark)
(2)In the TGN, the phosphorylated enzymes bind to M6P receptors, (1
mark) which direct the enzymes into vesicles coated with the clathrin. (1
mark)
(3)The clathrin lattice surrounding these vesicles is rapidly
depolymerized to its subunits, (1 mark) and the uncoated transport
vesicles fuse with late endosomes. (1 mark)
(4) Within this low-pH compartment, the phosphorylated enzymes
dissociate from the M6P receptors and then are dephosphorylated. (1
mark)
(5)The receptors recycle back to the Golgi. (1 mark)
(6)the enzymes are incorporated into a different transport vesicle that
buds from the late endosome and soon form a lysosome. (1 mark)
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95
5 Describe the process how free
ribosome become membranebound ribosome in detail(SIGNAL
HYPOTHESIS).
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(1)Once the ER signal sequence emerges from the ribosome, it is bound by
a signal- recognition particle (SRP) and causes a pause in translation.
(2)The SRP delivers the ribosome/nascent polypeptide complex to the SRP
receptor in the ER membrane.
(3) Transfer of the ribosome/nascent polypeptide to the translocon (protein
translocator) leads to opening of this translocation channel and insertion of
the signal sequence and adjacent segment of the growing polypeptide into
the central pore.
(4)Both the SRP and SRP receptor, once dissociated from the translocon
and then are ready to initiate the insertion of another polypeptide chain.
(5)Translation start again.
(6)As the polypeptide chain elongates, it passes through the translocon
channel into the ER lumen, where the signal sequence is cleaved by signal
peptidase and is rapidly degraded.
(7)The peptide chain continues to elongate as the mRNA is translated toward
the 3’ end.
(8)Once translation is complete, the ribosome is released, the remainder of
the protein is drawn into the ER lumen, the translocon closes, and返回
the
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protein assumes its native folded conformation.
6. Compare the structure,
diameter, protein subunit
and function among three
types of cytoskeleton.
98
Property
Microtubules
Structure
(2 mark)
Hollow tubes;
wall consists of 13
columns of
tubulin molecules
Diameter
(1 mark)
25 nm with 15 nm
lumen
Protein subunits
(2 mark)
Tubulin,
consisting of αtubulin and βtubulin
Main functions
(3 mark)
Maintenance of
cell shape
Cell motility
Chromosome
movements
Organelle
movements
Microfilaments
Two intertwined
strands of actin
Intermediate
Filaments
Fibrous proteins
supercoiled into
thicker cables
7 nm
8-12 nm
Actin
One of several
different proteins of
the keratin family,
depending on cell type
Maintenance of cell
shape
Changes in cell
shape
Muscle contraction
Cytoplasmic
streaming
Cell motility
Cell division
Maintenance of cell
shape
Anchorage of nucleus
and certain other
organelles
Formation of nuclear
lamina
99
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7 Describe the DNA packaging( multiple
coiling model)
100
7Nucleosomes are the basic unit of chromatin structure.I
NCLUDES 4types of Histones and 200bp DNA. Histones:
The most abundant proteins associated with eukaryotic DNA,
there are 5 types of histones,H1,H2A,H2B,H3,H4
CORE OF PERIPHERAL HISTON
H2B
H3
NUCLEO
SOME
DNA (146bp、1.75
H4
ROUND）
10nm
H2A
H2A
H
H4
1
H2B
HISTONE：2（H2A、H2B、H3 、
H4）OCTAMER
H3
CORE
LINKER DNA
（60bp）
H3
H2B
NUCLEOSO
H
ME 4
DNA MOLECULE：146bp、1.75
ROUND
H2A
H
H2A
1
H4
H2B
H3
HISTONE：H1
LINKER
DNA MOLECULE：60bp
101
•
•
•
•
•
•
Second level: 30nm _ diameter chromatin thread is second packing
structure of chromatin called solenoid, each 6 nucleosomes form a helical
line tube or loop domain.
To form a solenoid need a H1, at each end of loop domain, meanwhile
clamp or contact neighboring loop domains together and form solenoid,
inside diameter is 11nm, while outside is 30 nm. After second condensed
level, the length of DNA is further condensed 6 times.
Third level: after further folding, solenoid form the third packing level
supersolenoid
It is about 300-400 nm in diameter and 11-60 nm long, the DNA is
condensed by 40 times.
Fourth level: chromatid or chromosomeome the most condensed structure
of chromatin. we call it chromosome.
The length of chromosome is from 2-10nm long, thus after this folding, the
DNA is condensed about 5 times in length. After packing four times, the
DNA is condensed about 10000 times(7ⅹ6ⅹ40ⅹ5=8400), Finally
supersolenoid is folded again , and become a 5 micrometer long
chromosome, and it is easy to package into the nucleus
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