Cell and Molecular Bio Final Exam

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Which of the following transcription factors is needed to convert an adult cell into an induced pluripotent stem (iPS) cell? a) All of the above b) Klf4 c) Oct4 d) Sox2

a) All of the above

Can cell produce Y from X? a) True b) False

a) True

A multipotent cell _________. a) can give rise to some cell types in the body b) can only give rise to stem cells c) can give rise to all the tissues and cell types in the body d) is considered to be terminally differentiated

a) can give rise to some cell types in the body

Proteins that are fully translated in the cytosol and lack a sorting signal will end up in _____. a) the cytosol b) the mitochondria c) the interior of the nucleus d) transport vesicles

a) the cytosol

Which of the following hydrocarbon tail would yield the most highly mobile phospholipid? a) 24 carbons with 1 double bond b) 16 carbons with 2 double bonds c) 16 carbons with no double bonds d) 20 carbons with 2 double bonds

b) 16 carbons with 2 double bonds

an animal cell that has 8 chromosomes in G1phase. How many of each of the following structures will the cell have during mitosis?sister chromatids/ centromeres/ kinetochores/ centrosomes a) 8/16/8/2 b) 16/16/16/2 c) 16/8/16/2 d) 16/2/16/16

b) 16/16/16/2

The Akt kinase promote cell growth through the activation of _____ pathway. a) MAPK b) Bcl2 c) GLUT4 d) mTOR

d) mTOR

DNA isolated from mouse liver cells contains 26% A. What percent will be G? a) 26% b) uncertain c) 24% d) 74%

c) 24%

The following genes could become oncogene except ______. a) E2F b) cl2 c) BAD d) mTOR

c) BAD

Which of the following does not occur before a eukaryotic mRNA is exported from the nucleus? a) 3'-polyA added b) RNA splicing c) The ribosome binds to the mRNA. d) 5'-capping

c) The ribosome binds to the mRNA.

Which of the following statements about protein transport to mitochondria is TRUE? a) Proteins are translocated into the mitochondria as completely folded proteins. b) All the proteins in mitochondria need to be imported from cytosol. c) The signal that directs a protein to mitochondria is always cleaved off from the final folded protein. d) A protein has to be transported though the outer membrane and the inner membrane separately.

c) The signal that directs a protein to mitochondria is always cleaved off from the final folded protein.

In a experiment you add a ER-signal sequence to the N-terminus and a GFP tag to the C-terminus of a nuclear protein that contain NLS. You expect to see the green fluorescence a) In cytosol b) In nucleus c) In the lumen of ER d) Associated with ER membrane

c) in the lumen of ER

In stage 1 of photosynthesis, a proton gradient is generated and ATP is synthesized. Where do protons become concentrated in the chloroplast? a) thylakoid membrane b) stroma c) thylakoid space d) space between inner and out membranes

c) thylakoid space

Which of the following proteins can mediate the movement of sperm tails? a) myosin b) kinesin c) keratin d) dynein

d) dynein

Select the option below that most accurately predicts the relative rates of diffusion of these molecules across a phospholipid bilayer(fastest to slowest). a) alanine> ethanol > sodium > estrogen b) sodium > ethanol > alanine> estrogen c) estrogen > ethanol > sodium > alanine d) estrogen > ethanol > alanine> sodium

d) estrogen > ethanol > alanine> sodium

Which of the following is generally NOT a mechanism of gene silencing? a) DNA methylation b) transcription repressor c) RNAi d) histone acetylation

d) histone acetylation

You found a piece of gene sequence from NCBI database: 5'-ATACGT -3'Which of the following is the 1. Sequence of template strand? 2. Sequence of mRNA? 3. Coding sequence? a) 5'-ATACGT -3' b) 5'-AUACGU -3' c) 5'-ACGTAT -3' d) 5'-ACGUAU -3' e) 5'-TGCATA -3' f) 5'-UGCAUA -3'

1. c) 5'-ACGTAT -3' 2. b) 5'-AUACGU -3' 3. a) 5'-ATACGT -3'

1: To design a drug that can inhibit insulin secretion, which protein should NOT be chosen as the target? 2: To design a drug that can inhibit LDL uptake (endocytosis), which protein should NOT be chosen as the target? a) Tubulin b) Kinesin c) Dynein d) Clathrin

1. c) Dynein 2. b) Kinesin

1. To study the function of keratin, which of the following models can be chosen? 2. To study the function of lamin, which of the following models can be chosen? a) Yeast b) Drosophila c) Zebra fish d) Mouse e) B, C and D f) C and D g)All of them

1. f) C and D 2. g)All of them

Q: You want to clone a gene and produce the coded protein in bacteria. You isolate genomic DNA of this gene and insert it into plasmid, then transfer the plasmid into E coli. You found that the gene is successfully transcribed but no protein is synthesized in the bacteria. What's wrong?

Bacteria has no RNA splicing to remove introns. To express a transgene, cDNA sequence should be used.

To study a protein that controls development, which of the following model organism may NOT be chosen? a) Arabidopsis b) Drosophila c) Yeast d) C elegans

C) Yeast

Looking from the eyepieces, which color of fluorescence can you see?

Red

During fermentation, how many ATP will be generated from one glucose molecule? a) 2 b) 5 c) 10 d) 30

a) 2

Given the sequence of one strand of a DNA helix: 5' - GCATTCGTGGGTAG - 3' Give the sequence of the complementary strand and label the 5' and 3' ends. a) 5'-CTACCCACGAATGC-3' b) 5'-CUACCCACGAAUGC-3' c) 3'-CTACCCACGAATGC-5' d) 5'-CGTAAGCACCCATC-3'

a) 5'-CTACCCACGAATGC-3'

Which of the following statements is CORRECT? a) A gain-of-function mutation in only one allele of oncogene can stimulate cell survival or division. b) A loss-of-function mutation can convert a proto-oncogene into an oncogene. c) Mutations in the oncogenes induce tumorigenesis through producing unfunctional proteins. d) Loss-of-function mutations in a tumor suppressor gene make the coding protein hyperactive.

a) A gain-of-function mutation in only one allele of oncogene can stimulate cell survival or division.

Which of the following is NOT part of the process known as "oxidative phosphorylation"? a) ATP molecules are produced in the cytosol as glucose is converted into pyruvate. b) Cytochrome C serves as an electron carrier in the electron-transport chain. c) FADH2 and NADH transfer their electrons to the electron-transport chain. d) Molecular oxygen serves as a final electron acceptor.

a) ATP molecules are produced in the cytosol as glucose is converted into pyruvate.

Which of the following statement about receptor tyrosine kinases (RTKs) is TRUE? a) After signal molecule binding, RTKs are dimerized and phosphorylated. b) Phosphorylated serine residues on RTKs serve as docking sites for signaling complexes. c) A RTK always contains multiple cross membrane α helixes. d) The activated RTK can serve as docking site for Akt.

a) After signal molecule binding, RTKs are dimerized and phosphorylated.

Which of the following statements is TRUE? a) Covalent bonds can be established by condensation reaction, which release water molecules. b) Covalent bonds help assemble large protein complexes from protein subunits. c)Noncovalent bonds form only between different molecules d)Heat can unfold a protein molecule and broke it into small peptides.

a) Covalent bonds can be established by condensation reaction, which release water molecules.

In DNA replication the lagging strand is synthesized discontinuously at the replication fork because a) DNA polymerase can polymerize nucleotides only in the 5'-to-3' direction. b) DNA polymerase always falls off the template DNA every ten nucleotides or so. c) DNA polymerase needs RNA primer to start DNA synthesis. d) DNA polymerase removes the last few nucleotides synthesized whenever it stops.

a) DNA polymerase can polymerize nucleotides only in the 5'-to-3' direction.

You use GFP tag to track a protein that will ultimately be secreted from the cell. If all is functioning well, in which order (from first to last) do you expect to find the protein in the cell until it is secreted? a) ER → Golgi → secretory vesicle → outside of the cell b) ER → Golgi → endosome → outside of the cell c) Golgi → ER → secretory vesicle → outside of the cell d) nucleus → ER → Golgi → secretory vesicle → outside of the cell

a) ER → Golgi → secretory vesicle → outside of the cell

Which of the statement for euchromatin and heterochromatin is TRUE? a) Genes that are packaged into heterochromatin are generally silenced. b) Euchromatin fibers randomly distribute in the nucleus. c) Heterochromatin randomly distributes on chromosomes and in nucleus. d) All the euchromatin regions are highly opened and host expressing genes.

a) Genes that are packaged into heterochromatin are generally silenced.

Which of the following statements is TRUE? a) In anaphase B, microtubules associated with the cell cortex shorten. b) In anaphase A, chromosome movement is driven by shorten of aster microtubules. c) Anaphase A is driven by motor proteins kinesin and dynein. d) In anaphase A, both kinetochore and interpolar microtubules shorten.

a) In anaphase B, microtubules associated with the cell cortex shorten.

Cell movement involves the coordination of many events in the cell. Which of the following phenomena is NOT required for cell motility? a) Influx of Ca2+ into cytoplasm. b) Myosin-mediated contraction at the rear of the moving cell. c) Integrin association with the extracellular environment. d) Nucleation of new actin filaments.

a) Influx of Ca2+ into cytoplasm.

In a experiment, you treated cells with a drug that blocks ATP synthesis, which of the following processes will NOT be arrested immediately? a) Microtubule assembly b) Exocytosis c) Actin filament assembly d) Cell migration

a) Microtubule assembly

Plant cells need to maintain a proper membrane fluidity when the environmental temperature changes. Which of the following changes in plant cell membrane components will happen when time goes into the winter? a) more unsaturated phospholipids b) less unsaturated phospholipids c) more cholesterol d) less cholesterol e) more unsaturated phospholipids and less cholesterol f) less unsaturated phospholipids and more cholesterol g) no change

a) More unsaturated phospholipids

Which one has the lowest percentage of unsaturated phospholipids? a) Rattlesnake b) Penguin c) Salmon

a) Rattlesnake

What would be the most obvious outcome of repeated cell cycles consisting of S phase and M phase only? a) The cells produced would get smaller and smaller. b) Cells would not be able to replicate their DNA. c) Cells would get larger and larger. d) The mitotic spindle could not assemble.

a) The cells produced would get smaller and smaller.

Which of the statements below about intermediate filaments is FALSE? a) They are made of globular subunits. b) They can be found in the cytoplasm and the nucleus. c) They can be anchored to the plasma membrane at a cell-cell junction. d) Each filament is about 10 nm in diameter.

a) They are made of globular subunits.

After cell division, can daughter cells remember the specific gene expression pattern? a) Yes b) No

a) Yes

You discover that the underlying cause of a disease is a protein that is now less stable than the non-disease-causing version of the protein. This change is most likely to be due to ______. a) a mutation within a gene. b) horizontal gene transfer. c) gene duplication. d) a mutation within the regulatory DNA of a gene.

a) a mutation within a gene.

An adult hematopoietic stem cell found in the bone marrow ______________________. a) can undergo self-renewing divisions for the lifetime b) can produce only white blood cells c) will occasionally produce epidermal cells when necessary d) can produce only red blood cells

a) can undergo self-renewing divisions for the lifetime

Programmed cell death (apoptosis) can occur _______________. a) in some normal cells that are unwanted during development b) only when extrinsic death signals are present c) only in unhealthy or abnormal cells d) only during embryonic development

a) in some normal cells that are unwanted during development

Embryonic stem cells are such a powerful possible treatment for disease because they are______. a) pluripotent b) well understood c) derived from fetuses d) multipotent

a) pluripotent

When a terminally differentiated cell in an adult body dies, it can typically be replaced in the body by a stock of ________. a) proliferating precursor cells that are derived from adult stem cells b) induced pluripotent cells c) embryonic stem cells d) cells more apically located than the terminally differentiated cells

a) proliferating precursor cells that are derived from adult stem cells

Histone modifications can NOT ________. a) re-position nucleosomes using the energy of ATP b) retain after cell division c) serve as docking sites for other regulatory proteins d) directly affect nucleosome packaging

a) re-position nucleosomes using the energy of ATP

Which of the following compounds can be a potential anti-cancer drug? a) A compound that activates mTOR b) A compound that activates Ras-GAP c) A compound that activates Ras-GEF d) A compound that activates MAPKK

b) A compound that activates Ras-GAP

Which of the following statements about the cytoskeleton is FALSE? a) The cytoskeleton is made up of three types of protein filaments. b) Covalent bonds between protein monomers hold together cytoskeletal filaments. c) The cytoskeleton of a cell can change in response to signals. d) The cytoskeleton controls the location of organelles in eukaryotic cells.

b) Covalent bonds between protein monomers hold together cytoskeletal filaments.

Which of the following statements is TRUE? a) All cells will respond to the endocrine signals as endocrine molecules are broadcast throughout the body. b) Extracellular signal molecules that are hydrophilic must bind to a cell-surface receptor so as to signal a target cell. c) To function, all extracellular signal molecules must be transported by their receptor across the plasma membrane into the cytosol. d) A receptor bound by only one type of signal molecule can mediate only one kind of cell response. e) Each type of receptor must induce an independent signaling pathway and avoid interference with other intracellular signaling pathways.

b) Extracellular signal molecules that are hydrophilic must bind to a cell-surface receptor so as to signal a target cell.

The unwanted cytosolic proteins are sent to lysosome for digestion and re-use. a) True b) False

b) False

In an experiment, you treated cultured cells with colchicine, then analyzed these cells using flow cytometry. Which peak in the result would be dominant? a) I b) II c) III d) None of them

b) II

Irradiated mammalian cells usually stop dividing and arrest at a G1 checkpoint. Place the following events in the order in which they occur. I. production of p21 II. DNA damage III. inhibition of cyclin-Cdk complexes IV. activation of p53 a) II-IV-III-I b) II-IV-I-III c) I-II-III-IV d) II-I-IV-III

b) II-IV-I-III

During a drug screen you find a compound that can block the binding of Ca2+to troponin. Predict the effect of this drug. a) Muscle spasm b) Muscle paralysis c) Hypnosis d) No effect

b) Muscle paralysis

You have generated antibodies that recognize the extracellular domain of the Ca2+-pump. Adding these antibodies to living animal cells blocks the active transport of Ca2+from the cytosol into the extracellular environment. What do you expect to observe with respect to intracellular Ca2+level? a) Dramatically increases in the cytosol b) Remains low in the cytosol c) Decreases in ER d) Increases in Golgi

b) Remains low in the cytosol

Which of the following statements about membrane-enclosed organelles is TRUE? a) The nucleus is the only organelle that contains DNA. b) The membrane of nucleus is always continuous with the membrane of ER. c) The endomembrane system contains all of the membrane-enclosed organelles. d) All the membrane-enclosed organelles are surrounded by a double membrane.

b) The membrane of nucleus is always continuous with the membrane of ER.

Which of the following means of transport would most likely be used for moving an amino acid from a low concentration on the outside to a high concentration on the inside of a cell? a) active transport through a channel b) active transport though a transporter c) free diffusion d) passive transport through a transporter

b) active transport though a transporter

Which of the following molecules will NOT be produced in fermentation? a) NADH b) actyle CoA c) ATP d) pyruvate

b) actyle CoA

A cell with mutated lamins that cannot be phosphorylated in M phase will be unable to a) begin to grow microtubules for spindle assembly. b) disassemble its nuclear lamina at prometaphase. c) reassemble its nuclear envelope at telophase. d) condense its chromosomes at prophase.

b) disassemble its nuclear lamina at prometaphase.

Which of the following processes do NOT take place in the mitochondria? a) ATP generation by ATP synthase b) glycogen breakdown c) citric acid cycle d) oxidation of fatty acids to acetyl CoA

b) glycogen breakdown

The Retinoblastoma (Rb) protein blocks cells from entering the cell cycle by _______________. a) activating cell death b) inhibiting cyclin transcription c) degrading cyclins d) phosphorylating Cdk

b) inhibiting cyclin transcription

A malignant tumor is more dangerous than a benign tumor because its cells ________________. a) cause neighboring normal cells to mutate b) invade other tissues c) attack and phagocytose neighboring cells d) proliferate faster

b) invade other tissues

Which of these is NOT the function of cell surface sugars? a) protecting cell surface with a slimy layer b) metabolism to produce energy c) cell to cell contact and adherence d) cell recognition

b) metabolism to produce energy

Progression through the cell cycle requires a cyclin to bind to a Cdk because _________. a) the cyclins are the molecules with the enzymatic activity in the complex b) the binding of a cyclin to Cdk is required for Cdk enzymatic activity c) cyclin binding inhibits Cdk activity until the appropriate time in the cell cycle d) without cyclin binding, a cell-cycle checkpoint will be activated

b) the binding of a cyclin to Cdk is required for Cdk enzymatic activity

Assuming that a UV light with wavelength of 300 nm is used for microscopy. The resolution limit of this microscope should be _______. a) 600 nm b) 300 nm c) 150 nm d) 200 nm

c) 150 nm

To label a protein, you used a green fluorescent dye with excitation wavelength of 500 nm. Which of the following emission wavelength you may choose? a) 500 nm b) 460 nm c) 540 nm d) All of them

c) 540nm

Suppress of apoptosis can promote cancer cell survival. Which of the following compound could be an anti-cancer drug? a) A compound that inhibits Bax b) A compound that inhibits Bad c) A compound that inhibits Bcl2 d) A compound that inhibits Fas-receptor

c) A compound that inhibits Bcl2

Which of the following compounds can NOT be a potential anti-cancer drug? a) A compound that blocks association of Ras-GEF with RTK b) A compound that inhibits Ras-GEF c) A compound that inhibits Ras-GAP d) A compound that inhibits MAPKKK

c) A compound that inhibits Ras-GAP

Which of the following statements is FALSE? a) The size of a nucleosome is around 11 nm. b) A nucleosome contains a histone core with DNA wrapped around it approximately two times. c) A histone core contains two of each of the core histones (H1, H2, H3, H4). d) Chromatins are present in eukaryotic cells, but not in prokaryotic cells.

c) A histone core contains two of each of the core histones (H1, H2, H3, H4).

These phase contrast images shows a living cell at different stages in M phase. Oder them into the correct sequence. a) A-B-C-D-E-F b) D-A-C-E-B-F c) E-D-C-A-F-B d) B-E-A-D-C-F

c) E-D-C-A-F-B

You made a transgene encoding a cell surface protein fused with GFP at C-terminal (Why?)and will express it in cultured cells. Predict the cellular components that are labeled by green fluorescence. a) cell membrane b) Golgi, vesicles, cell membrane c) ER, Golgi, vesicles, cell membrane d) ER, Golgi, vesicles, endosome, lysome, cell membrane e) cytosol, ER, Golgi, vesicles, cell membrane f) nucelus, cytosol, ER, Golgi, vesicles, cell membrane

c) ER, Golgi, vesicle, cell membrane

Identify the phases of cell populations in I/II/III. a) G1/S/G2 b) S/G1/G2 c) G1/G2/S d) G2/G1/S

c) G1/G2/S

In a experiment you add a ER-signal sequence to the N-terminus and a GFP tag to the C-terminus of a cytosolic protein. You expect to see the green fluorescence a) In cytosol b) In nucleus c) In the lumen of ER d) Associated with ER membrane

c) In the lumen of ER

To design a drug that can inhibit cell migration, which protein may NOT be chosen as the target? a) Actin b) ARP c) Kinesin d) Myosin e) Integrin f) Filamin

c) Kinesin

COVID-19 is a retrovirus that integrates into the host cell's genome and will eventually replicate, produce viral proteins, and ultimately escape from the host cell. Which of the following proteins is not encoded in the virus genome? a) reverse transcriptase b) Spike (adhere protein on virus surface) c) RNA polymerase d) envelope protein

c) RNA polymerase

Which one has the highest percentage of unsaturated phospholipids? a) Rattlesnake b) Penguin c) Salmon

c) Salmon

Which one has the lowest percentage of cholesterol? a) Rattlesnake b) Penguin c) Salmon

c) Salmon

Which of the following amino acid contains hydrophilic side chain? a) Phe b) Met c) Thr d) Val

c) Thr

Which of the following statements is false ? a) CO2and O2are water-soluble molecules that diffuse freely across cell membranes. b) Ion channels are one of the passive forms of cross-membrane transport. c) Transporters are similar to channels, except that they have larger gates, allowing folded proteins as well as smaller organic molecules to pass through them. d) Cells expend energy in the form of ATP hydrolysis so as to maintain ion concentrations inside the cell that differ from those found outside the cell.

c) Transporters are similar to channels, except that they have larger gates, allowing folded proteins as well as smaller organic molecules to pass through them.

In a benign tumor we may found the following defected programs except ________. a) suppressed apoptosis b) excessive cell growth c) enhanced cell migration d) misregulated cell cycle

c) enhanced cell migration

RNA in cells differs from DNA in that ___________________. a) it contains the base uracil, which pairs with cytosine. b) the sugar ribose contains fewer oxygen atoms than does deoxyribose. c) it is single-stranded and can fold up into a variety of structures. d) it is single-stranded and cannot form base pairs.

c) it is single-stranded and can fold up into a variety of structures.

Macromolecules in the cell can often interact transiently as a result of noncovalent interactions. These weak interactions also produce stable, highly specific interactions between molecules. Which of the factors below is the most significant in determining whether the interaction will be transient or stable? a) all of them b) the size of each molecule c) the surfaces on the two molecules are complementary (match) d) the number of polar regions on the surface of each molecule

c) the surfaces on the two molecules are complementary (match)

Which of the following mutations would lead to an excess in the amount of glucose in skeletal muscle cells? a) A GPCR mutant form that loses the binding ability to adenaline b) A G-protein mutant form that loses GTP-binding ability c) A PKA mutant form that loses cAMP-binding ability d) A PKA mutant form in which the inhibitory subunits lose the binding ability to the kinase subunits.

d) A PKA mutant form in which the inhibitory subunits lose the binding ability to the kinase subunits.

Which of the following will be most likely induced by an insertion of one base pair into an exon? a) No change in the protein sequence as it could be a nonsense mutation. b) No change in the protein sequence as the insertion may be removed during mRNA splicing. c) Producing a protein with one amino acid changed. d) Producing a protein with many amino acids changed.

d) Producing a protein with many amino acids changed.

Which of the following statements is TRUE? a) Gene sequences on chromosomes can be directly translated into protein sequences b) All genes start with ATG c) All mRNAs start with AUG d) Protein syntheses start with Met e) All proteins start with Met

d) Protein syntheses start with Met

Which of the following statements is TRUE? a) The more nucleotides there are in an organism's genome, the more genes there will be in its genome. b) Because the fly Drosophila melanogaster and humans diverged from a common ancestor so long ago, any two fly genes will show more similarity to each other than it will to a human gene. c) Two closely related organisms are more likely to have a genome of the same size than a more evolutionarily diverged animal. d) The sequence of exons in many genes is conserved in vertebrates.

d) The sequence of exons in many genes is conserved in vertebrates.

Which of the statements about phospholipids, glycolipids and cholesterol is TRUE? a) They are the components of all eukaryotic membranes. b) All of them. c) They all contain two hydrophobic tails. d) They are all amphipathic molecules.

d) They are all amphipathic molecules.

Which property below is TRUE of enzymes? a) They help produce more products from substrates. b) They alter the delta-G of a reaction. c) They are used up in a reaction. d) They lower the activation energy of the reaction.

d) They lower the activation energy of the reaction.

Which of the following mechanisms can help produce gene family and super family? a) gene duplication b) gene mutation c) exon shuffling d) all of them

d) all of them

Which of the following processes can be found in plant cells? a) citric acid cycle b) oxidative phosphorylation c) light reaction d) all of them

d) all of them

A polar molecule can form _______ with water molecules? a) covalent bonds b) ionic bonds c) hydrophobic bonds d) hydrogen bonds

d) hydrogen bonds

Which type of proteins can be removed from membrane most easily? a) transmembrane b) monolayer associated c) lipid-linked d) protein-attached

d) protein-attached

Proteins that are fully translated in the cytosol do not end up in _______. a) the cytosol b) the mitochondria c) the interior of the nucleus d) transport vesicles

d) transport vesicles

Which of the following 20 aa sequences is likely a cross membrane structure? P: polar amino acid N: nonpolar amino acid a)PPPPPPNNNNNNNNPPPPPP b)NNNNNNNNNNNNNNNNNNNN c)PNPNPPPPPNNNPPNNNNNP d)NNPNNPNNPNNPNNPNNPNN e) A & B f) B & D

f) B&D

Which of the following compounds can be a potential anti-cancer drug? A compound that inhibit a) p53 b) Rb c) E2F d) S-Cdk e) A and B f) C and D

f) C and D

Your friend works in a lab that is studying why a particular mutant strain of Drosophila grows an eye on its wing. Your friend discovers that this mutant strain of Drosophila is expressing a transcription factor incorrectly. In the mutant Drosophila, this transcription factor, which is normally expressed in the primordial eye tissue, is now misexpressed in the primordial wing tissue, thus turning on transcription of the set of genes required to produce an eye in the wing primordial tissue. If this hypothesis is true, which of the following types of genetic change would most likely lead to this situation? a) A mutation within the transcription factor gene that leads to a premature stop codon after the third amino acid. b) A mutation within the transcription factor gene that leads to a substitution of a positively charged amino acid for a negatively charged amino acid. c) A mutation in the TATA box of the gene. d) A mutation within an upstream regulatory element of the gene.

d) A mutation within an upstream regulatory element of the gene.

Working in a company, you try to develop a drug to inhibit the activity of an enzyme that plays important role in cancer. This enzyme is an allosteric protein. You could design a compound that a) can compete with the substrate binding to this enzyme. b) mimics the structure of the ligand that binds to this enzyme. c) can bind to the ligand and prevent its binding to this enzyme. d)All of above.

d) All of the above.

Which of the following statement about second messenger is TRUE? a) The G-protein-PLC pathway theoretically synthesize the same amount of DAG and IP3. b) IP3 can trigger Ca2+ release from endoplastic reticulum. c) Each PKA is bond and activated by 4 cAMP molecules. d) All of them.

d) All of them.

Which of the following statements about apoptosis is TRUE? a) Bax and Bak promote apoptosis by binding to procaspases in the apoptosome. b) The Fas ligand and Fas receptor co-work to inhibit apoptosis. c) Cells that constitutively express Bcl2 will be more prone to undergo apoptosis. d) Apoptosis can be promoted by the release of cytochrome c into the cytosol from mitochondria.

d) Apoptosis can be promoted by the release of cytochrome c into the cytosol from mitochondria.

In a experiment you add a start-transfer sequence to the N-terminus and a GFP tag to the C-terminus of a cytosolicprotein. You expect to see the green fluorescence a) In cytosol b) In nucleus c) In the lumen of ER d) Associated with ER membrane

d) Associated with ER membrane

A muscle is contracted when which of the following occurs? a) Calcium levels in the muscle cell are low. b) Troponin binds to myosin. c) Troponin and tropomyosin block the myosin binding site on actin. d) Calcium binds to troponin.

d) Calcium binds to troponin.

In a SDS-PAGE protein gel electrophoresis experiment, SDS can do all these works except_________. a) Coating proteins with negative charges b) Breaking membrane c) Unfolding proteins d) Degrading proteins

d) Degrading proteins

Which of the following is FALSE of the sodium-potassium pump? a) It creates an electrochemical gradient across the cell membrane. b) The sodium gradient created by the pump is used for glucose absorption in the gut. c) It has enzyme activity to catalyze hydrolysis of ATP to ADP. d) It transports 2 sodium ions out of the cell and 3 potassium ions into the cell each time.

d) It transports 2 sodium ions out of the cell and 3 potassium ions into the cell each time.

Which of the following statements about genome is NOT true? a) The coding sequence of a gene can be on either of the DNA strand. b) Human genome is distributed on 46 chromosomes in most normal cells. c) Some genes do not code proteins. d) Most of the human genome code for proteins.

d) Most of the human genome code for proteins.

Which of the following happens when a G-protein-coupled receptor activates a G protein? a) The GDP bound to the α subunit is phosphorylated to form bound GTP. b) The α subunit exchanges its bound GDP for GTP, which activates the α subunit and inactivates the βγcomplex. c) The β subunit exchanges its bound GDP for GTP. d) None of the above.

d) None of the above.

Which of the following happens when a G-protein-coupled receptor activates a G protein? a) It activates the α subunit and inactivates the βγ complex. b) The GDP bound to the α subunit is phosphorylated to form bound GTP. c) G-protein is disassembled into three subunits, each of which induces a separate pathways. d) None of them.

d) None of them.


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