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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 roundsingle choose questions

The rules of the roundThe 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 Choose below pleaseplease

banana

lemon

Water melon

apple

orange

cake

tomato

Mahmud tea

juice

milk

math

physics

biology

surgeon

Table tennis

Badminton

Baseball

Football

1 2 54 63

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 返回

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• 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.

返回Answer ：D

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•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

返回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

返回Answer ：D

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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.

返回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.

返回Answer ：C

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• 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

Answer ：E

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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

返回Answer ：E

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• 10 What is usually the major component of plasma membranes of Eukaryotes?•A. Phospholipids •B. Fats •C. Cholesterol •D. Nucleic acids •E. Triglycerides

返回Answer ：A

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• 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.

返回Answer ：C

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• 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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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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14. Which of the following statements about nucleoli is true?A. Nucleoli are membrane-bounded structures present in the nucleusB. 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 synthesisD. The DNA of nucleoli encodes the cells tRNA genesE. All of the above

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Answer ： D

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15.Actin filaments are destabilized by: A. phalloidin

B. actinomysin D C. colcemid

D. cytochalasin E. taxol

Answer ： D

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16.O-linked glycosylation occurs on which amino acids?

A.serine B. asparagines C. tyrosine D. threonine E. A and D

E 返回

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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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The rules of contestThe rules of contest ：：Each group must be answer Each group must be answer one questionone question ，， group group members can discuss in I members can discuss in I minuteminute ，， one of the contestant one of the contestant answer questionanswer question ，， each each correct question 100 correct question 100 marked ,if wrong no discount.marked ,if wrong no discount.

The Second Round

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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？

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Answer:(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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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 6 Describe briefly the functions Describe briefly the functions of rough ERof rough ER ..

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Answer:Answer: Functions of RER: Functions of RER: (1)Proteins synthesized on (1)Proteins synthesized on ribosomes of RER. ribosomes of RER. (2)Modification and processing of (2)Modification and processing of newly synthesized proteins: newly synthesized proteins: glycosylation. glycosylation. (3)Quality control of newly (3)Quality control of newly synthesized proteins. synthesized proteins. (4)Synthesis of membrane lipids. (4)Synthesis of membrane lipids.

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7 7 Describe briefly the Describe briefly the ultrastructure and functions ultrastructure and functions of Golgi complex. of Golgi complex.

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Answer:The structure of Golgi complex: Cis face and trans face; Cis face and trans face; Cis Golgi network(CGN), Cis Golgi network(CGN), cisterna(cis, medial, trans),cisterna(cis, medial, trans), trans Golgi network(TGN).trans Golgi network(TGN). The Functions of Golgi complex: (1)Glycosylation.(1)Glycosylation. (2)Protein sorting(2)Protein sorting (3)Cell secretion (3)Cell secretion (4)Biogenesis of Lysosomes. (4)Biogenesis of Lysosomes.

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• The rules of the The rules of the rushing to answer questions ：：

• one of the contestant answer one of the contestant answer questionquestion ，， who presses button first!who presses button first!

• each correct question 50 marked ,each correct question 50 marked ,

• if wrong 50 marks discount.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.

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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 False6.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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9.The inner surface of the nuclear envelope is lined by .

Fill in the blank

nuclear lamina nuclear lamina

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10.Heterochromatin can be divided into two classes: constitutive and .

facultative

Fill in the blank

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11 Most organelles in endomembrane system are part of a system in which vesicles move between compartments.

Fill in the blank

Dynamic

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12. ( ) are heterogeneous mixtures of similar-sized vesicles, formed from membranes of the ER and Golgi complex.

Fill in the blank

MicrosomesMicrosomes

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•Audients answer questionsAudients 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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5.5.The chromatins which are light-The chromatins which are light-

staining, less staining, less condensedcondensed and and have transcriptional activity are have transcriptional activity are heterochromatin.heterochromatin.

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6.Which of the following are NOT components of the cytoskeleton?

A.actin filaments B. collagen fibers C. microtubulesD. 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 gameThe rules of the game ：：Each participating team Each participating team optional choose different optional choose different valued (200marks or valued (200marks or 300marks)one question300marks)one question and and after discussions for one after discussions for one minute in team, choose one minute in team, choose one participant to answer the participant to answer the question. question.

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Choose Choose meme！！

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1 What distinguishes the two main types of cells.

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1ANSWER: 返回

prokaryote eukaryote

size small large

nucleus absent present

cell division simple fission mitosis, meiosis

inner membrane

rare complex

ribosome 70S 80S

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What is the difference between DNA and RNA?

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sugar base strand location

DNA deoxyribose

A , G, C, T

double nucleus

RNA ribose A, G, C, U

single cytoplasm

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3List the four different nucleotides found in DNA, the typical Watson-Crick 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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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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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. 返回

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7Describe briefly 7Describe briefly the functions of the functions of smooth ER.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 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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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 cis-

Golgi 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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5 Describe the process how free ribosome become membrane-bound 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 the

protein assumes its native folded conformation. 返回

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6. Compare the structure, diameter, protein subunit and function among three types of cytoskeleton.

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Property Microtubules MicrofilamentsIntermediate

Filaments

Structure(2 mark)

Hollow tubes; wall consists of 13 columns of tubulin molecules

Two intertwined strands of actin

Fibrous proteins supercoiled into thicker cables

Diameter(1 mark)

25 nm with 15 nm lumen

7 nm 8-12 nm

Protein subunits(2 mark)

Tubulin, consisting of α-tubulin and β-tubulin

Actin

One of several different proteins of the keratin family, depending on cell type

Main functions(3 mark)

Maintenance of cell shapeCell motilityChromosome movementsOrganelle movements

Maintenance of cell shapeChanges in cell shapeMuscle contractionCytoplasmic streamingCell motilityCell division

Maintenance of cell shapeAnchorage of nucleus and certain other organellesFormation of nuclear lamina

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7 Describe the DNA 7 Describe the DNA packaging( multiple coiling packaging( multiple coiling model)model)

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7Nucleosomes are the basic unit of chromatin structure.INCLUDES 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

H4

DNA (146bp 、 1.75 ROUND）

H3

H4H3

H2AH2A

H2B

H2B

H4H3

H3H4

H2AH2A

H2B

H2B

10nm

LINKER DNA（ 60bp）

H

1

H

1

NUCLEOSOME

CORE

LINKER

DNA MOLECULE ：146bp 、 1.75 ROUND

HISTONE ：2 （ H2A 、 H2B 、 H3 、 H4 ） OCTAMER

HISTONE ： H1

DNA MOLECULE ： 60bp

NUCLEOSOME

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• 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(7 6 40 5=8400), Finally ⅹ ⅹ ⅹsupersolenoid is folded again , and become a 5 micrometer long chromosome, and it is easy to package into the nucleus

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