cell biology final password is cell
During the action potential propagation on neuron cell, which of the following best describes the voltage changes in one plasma membrane region? -60 mV > -40 mV > 0 mV > +40 mV > -60 mV -40 mV > 0 mV > +40 mV > -40 mV 0 mV > +40 mV > +60 mV > +40 mV > 0 mV -60 mV > -40 mV > 0 mV > -40 mV > -60 mV
-60 mV > -40 mV > 0 mV > +40 mV > -60 mV
Which of the following hydrocarbon tail would yield the most highly mobile phospholipid (listed as number of carbons and number of double bonds, respectively)? 15 carbons with 2 double bonds 16 carbons with no double bonds 24 carbons with 1 double bond 20 carbons with 2 double bonds
15 carbons with 2 double bonds
Consider an animal cell that has 8 chromosomes in G1 phase. How many of each of the following structures will the cell have at mitotic prophase? sister chromatids / centromeres / kinetochores / centrosomes 8 / 16 / 8 / 2 16 / 16 / 16 / 2 16 / 8 / 16 / 2 16 / 2 / 16 / 16
16 / 16 / 16 / 2
Given the sequence of a coding strand: 5' - GCATTCGTGGGTAG - 3' Give the sequence of mRNA and label the 5' and 3' ends. 5'-CTACCCACGAATGC-3' 5'- GCAUUCGUGGGUAG -3' 5'-CGUAAGCACCCAUC-3' 5'-CUACCCACGAAUGC-3'
5'- GCAUUCGUGGGUAG -3'
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. 5'-CGTAAGCACCCATC-3' 5'-CUACCCACGAAUGC-3' 3'-CTACCCACGAATGC-5' 5'-CTACCCACGAATGC-3'
5'-CTACCCACGAATGC-3'
Place the following events of M phase into the correct order. 1. Alignment of the chromosomes at the spindle equator 2. Attachment of microtubules to chromosomes 3. Breakdown of nuclear envelope 4. Reformation of the nuclear envelope 5. Condensation of the chromosomes 6. Separation of sister chromatids 3,5,2,1,6,4 5,3,1,2,6,4 5,3,2,1,6,4 3,5,1,2,6,4
5,3,2,1,6,4
Which of the following compounds can be a potential anti-cancer drug? A compound that activates Ras-GEF A compound that activates Ras-GAP A compound that activates MAPKK A compound that activates mTOR
A compound that activates Ras-GAP
Which of the following statements is CORRECT? Loss-of-function mutations in a tumor suppressor gene make the coding protein hyperactive. A loss-of-function mutation can convert a proto-oncogene into an oncogene. A gain-of-function mutation in only one allele of oncogene can stimulate cell survival or division. Mutations in the oncogenes and tumor suppressor genes induce tumorigenesis through disrupting either the protein level or the protein activity.
A gain-of-function mutation in only one allele of oncogene can stimulate cell survival or division.
Which of the following statements is FALSE? A histone core contains two of each of the core histones (H1, H2, H3, H4). Chromatins are present in eukaryotic cells, but not in prokaryotic cells. The N-terminal tails of core histones can be covalently modified. A nucleosome contains a histone core with DNA wrapped around it approximately two times.
A histone core contains two of each of the core histones (H1, H2, H3, H4).
Which of the following statements is FALSE? Cancer cells proliferate indefinitely, presumably related with the stabilization of telomeres. A loss-of-function mutation of telomerase will convert a normal cell to a cancer cell. Telomerase carries a RNA template, synthesizes and extends template DNA strand at telomere. Somatic cells only divide a limited number of cycles, likely due to the shorten of telomeres.
A loss-of-function mutation of telomerase will convert a normal cell to a cancer cell.
Which of the following statements about cancer is FALSE? Carcinogens cause cancer by changing the nucleotide sequence of DNA. A mutation in a single cancer-critical gene is sufficient to convert a normal cell into a cancer cell. Many cancer cells have abnormal chromosomes representing genetic instability. Viruses cause some cancers.
A mutation in a single cancer-critical gene is sufficient to convert a normal cell into a cancer cell.
23. DNA isolated from mouse liver cells contains 26% A. What percent will be G? A. 24% B. 26% C. 74% D. 13%
A. 24%
28. What is NOT true for euchromatinand heterochromatin? A. All the euchromatinregions are highly opened and contain expressing genes. B. Genes that are packaged into heterochromatin are generally silenced. C. Specific histone modifications can trigger formation and spreading of heterochromatin. D. Both euchromatinand heterochromatin are packaged into highly condensed mitotic chromosomes during cell division.
A. All the euchromatinregions are highly opened and contain expressing genes.
9. Which of the following statements is TRUE? A. Covalent bonds can be established by condensation reaction, which release water molecules. B. Heat can unfold a protein molecule and broke it into small peptides. C. The folding of a protein can be mediated only by noncovalent bonds. D. Covalent bonds help assemble large protein complexes from protein subunits.
A. Covalent bonds can be established by condensation reaction, which release water molecules.
2. To study a protein that controls the phosphorylation of RNA polymerase II, which of the following model organism can NOT be chosen? A. E. Coli B. Yeast C. Drosophila D. Arabidopsis
A. E. Coli
45. Which of the following statements about CRISPR-Cas9 is FALSE? A. It is a defense mechanism originally discovered in eukaryotic cells. B. Cas9 is an enzyme that can cleave DNA. C. guide RNA directs Cas9 to specific locus on DNA D. CRISPR-Cas9 can be applied for both gene knockout and gene activation.
A. It is a defense mechanism originally discovered in eukaryotic cells.
33. Which of the following histone modifications can NOT be a mark for gene silencing? A. acetylation B. phosphorylation C. methylation D. all off above
A. acetylation
18. Prokaryotic cells do NOTcontain __________. A. chromatin B. DNA polymerase C. ribosome D. tRNA
A. chromatin
8. In the backbone of a polypeptide, amino acids are connected by A. covalent bonds B. ionic bonds C. hydrogen bonds D. hydrophobic bonds
A. covalent bonds
30. Which of the following is NOT an epigenetic mechanism? A. mRNA splicing B. DNA methylation C. histone methylation D. noncoding RNA
A. mRNA splicing
17. Which of the following structure can be a cross-membrane domain? A. α-helix B. β-sheet C. coiled-coil D. all of above
A. α-helix
Researchers studying vesicular transport assembled several transport components in vitro (in a test tube). They set up the microtubules, then added vesicles and kinesin. When they put everything together, there was no movement of transport vesicles along microtubule. What were they missing? ATP GTP SNARE Ca2+
ATP
Which of the following statements is FALSE? Most G-protein-coupled receptors are multipass transmembrane proteins with 7 α-helixes. Activated G protein produces 3 separate subunits that function independently. Each calmodulin can bind to 4 calcium ions. Receptor tyrosine kinases (RTK) always form dimers after binding with signal molecules.
Activated G protein produces 3 separate subunits that function independently.
Which of the following transcription factors is needed to convert an adult cell into an induced pluripotent stem (iPS) cell? Sox2 Klf4 Oct4 All of the above
All of the above
Which of the following statements about apoptosis is TRUE? Cells that constitutively express Bcl2 will be more prone to undergo apoptosis. Bax and Bak promote apoptosis by binding to procaspases in the apoptosome. The Fas ligand and Fas receptor work to inhibit apoptosis. Apoptosis can be promoted by the release of cytochrome c into the cytosol from mitochondria.
Apoptosis can be promoted by the release of cytochrome c into the cytosol from mitochondria.
26. Which of the following statements is FALSE? A. Chromatins are present in eukaryotic cells, but not in prokaryotic cells. B. A histone core contains two of each of the core histones (H1, H2, H3, H4). C. A nucleosome contains a core of histone with DNA wrapped around it approximately two circles. D. The N-terminal tails of core histones can be covalently modified.
B. A histone core contains two of each of the core histones (H1, H2, H3, H4).
48. Which of the following statement is TRUE? A. Restriction enzymes digest DNA into single nucleotides. B. A primer is needed for DNA sequencing. C. To clone a eukaryotic gene, we should use yeast instead of E coli. D. All of above.
B. A primer is needed for DNA sequencing.
21. Which of the following statements about genome is NOT true? A. Most of the human genes contain intron. B. All of the human genes code for proteins. C. Many human genes are believed to undergo alternative splicing. D. Human genome is distributed on 46 chromosomes in most normal cells.
B. All of the human genes code for proteins.
1. In , each individual cells can be tracked during development. A. zebrafish B. C. elegans C. Drosophila D. Arabidopsis
B. C. elegans
24. Which of the following can be found in the backbone of DNA? A. Ribose B. Deoxyribose C. Thymine D. Uracil
B. Deoxyribose
29. Which of the following can NOT be a mechanism of gene silencing? A. Recruitment of a chromatin remodeling complex to reposition nucleosomes. B. Generation of histone acetylation to the promoter region. C. Repressor inhibits an activator to keep the transcription off. D. RNAi induced heterochromatin formation.
B. Generation of histone acetylation to the promoter region.
46. Which of the statements about genomic DNA and cDNA is TRUE? A. cDNA is produced through mRNA splicing. B. Genomic DNA sequences always contain noncoding sequences. C. Genomic DNA sequences can be directly used to predict protein sequences. D. All of above.
B. Genomic DNA sequences always contain noncoding sequences.
37. Which of the following statements about the transcription regulators is TRUE? A. Most transcription factors bind to the small groove of DNA. B. Most transcription factors function as dimer. C. Transcription factors tend to bind anywhere of DNA. D. Transcription regulators must bind to the promoter so that Pol II complex can be recruit to the transcription starting site.
B. Most transcription factors function as dimer.
5. Which of the following is a characteristic of electron microscopy? A. Is easy and inexpensive B. Super high resolution C. Has available dyes for staining cells D. Can be used on live cells
B. Super high resolution
12. Which of the following statements is FALSE? A. A protein chain starts with an amino group and ends in a free carboxyl group. B. The sequence of the atoms in the polypeptide backbone varies among different proteins. C. In a higher temperature, more chaperons can be synthesized to guide the folding of proteins. D. The structure and function of a protein are determined mainly by the side chains of amino acids.
B. The sequence of the atoms in the polypeptide backbone varies among different proteins.
Which of the following amino acid contains hydrophilic side chain? C. Val A. Phe D. Met B. Thr
B. Thr
27. Which type of RNA in the following controls gene silencing? A. rRNA B. miRNA C. snRNA D. tRNA
B. miRNA
Energy diagrams for the conversion of a substrate S into a product P are shown in the following figure. The left diagram shows the original energy profile for the reaction. If the reaction is catalyzed by an enzyme, choose a matching altered energy diagram from the figure. D C B A
C
25. Given the sequence of one strand of a DNA helix: 5'-GCATTCGTGGGTAG-3' Give the sequence of the complementary strand. A. 5'-CGTAAGCACCCATC-3' B. 5'-CUACCCACGAAUGC-3' C. 5'-CTACCCACGAATGC-3' D. 5'-GCATTCGTGGGTAG-3'
C. 5'-CTACCCACGAATGC-3'
31. Which of the following DNA fragments (show only one strand) needs a higher temperature for denaturation? A. ATCGGCTAATCG B. ATATCGTTTAAA C. CCCGGGTAGGCCGCGG D. CATACGTTTAAATTAAAT
C. CCCGGGTAGGCCGCGG
36.Which of the following mechanisms can NOT induce chromatin condensation ? A. histone methylation B. DNA methylation C. CRISPR-Cas9 D. RNAi
C. CRISPR-Cas9
44. Which of the following is NOT a mechanism that mediate RNAi? A. RNA cleavage B. translational repression C. DNA cleavage D. heterochromatin formation
C. DNA cleavage
34. About the difference between eukaryotic transcription and prokaryotic transcription, which of the following statements is FALSE? A. Eukaryotic transcription occurs in the nucleus, prokaryotic transcription in the cytoplasm B. Eukaryotic mRNAs have a 5' cap and a 3' polyAtail, prokaryotic mRNAs don't. C. Eukaryotic initiation requires specific DNA sequences at promoter, prokaryotic initiation doesn't. D. Prokaryotic transcription can be coupled with translation, eukaryotic transcription cannot.
C. Eukaryotic initiation requires specific DNA sequences at promoter, prokaryotic initiation doesn't.
7. Which of the following statements about fluorescence microscopy is FALSE? A. The resolution limit of a regular fluorescence microscopy is around 200 nm. B. Confocal microscopy improves the resolution of fluorescence microscopy by excluding out-of-focus lights. C. The excitation wavelength of GFP is longer than its emission wavelength. D. GFP protein can be used to track the expression of specific genes or proteins in living cells.
C. The excitation wavelength of GFP is longer than its emission wavelength.
38. Which of the following statements about the translation is TRUE? A. The start and stop codons do not code any amino acids. B. Among the three sites (A, P, E) on ribosome, E site is the entrance of charged tRNA. C. The newly synthesized peptide always begins with methionine (Met). D. To ensure a smooth and faithful translation, the assembly of a ribosome on mRNA prevents the binding of other ribosome units to the same mRNA.
C. The newly synthesized peptide always begins with methionine (Met).
43. Which of the following mechanisms can NOT activate a transcription factor? A. To activate the gene that codes this transcription factor. B. To remove inhibitors that interact with this transcription factor. C. To relocate this transcription factor to cytosol. D.To inhibit proteasomaldegradation of this transcription factor.
C. To relocate this transcription factor to cytosol.
Which of the following statements about the cytoskeleton is FALSE? Covalent bonds between protein monomers hold together cytoskeletal filaments. The cytoskeleton is made up of three types of protein filaments. The cytoskeleton controls the location of organelles in eukaryotic cells. The cytoskeleton of a cell can change in response to signals.
Covalent bonds between protein monomers hold together cytoskeletal filaments.
Which of the following statements is TRUE? Heat can unfold a protein molecule and broke it into small peptides. The folding of a protein can only be mediated by noncovalent bonds. Covalent bonds can be established by condensation reaction, which release water molecules. Covalent bonds help assemble large protein complexes from protein subunits.
Covalent bonds can be established by condensation reaction, which release water molecules.
22. Given the sequence of a coding strand: 5'-GCATTCGTGGGTAG-3' Give the sequence of the mRNA and label the 5'and 3' ends. A. 5'-CGUAAGCACCCAUC-3' B. 5'-CUACCCACGAAUGC-3' C. 5'-CTACCCACGAATGC-3' D. 5'-GCAUUCGUGGGUAG-3'
D. 5'-GCAUUCGUGGGUAG-3'
49. To study the functions of a novel protein, which of the following approaches can be employed? A. imaging assays to check its subcellular localization B. genetic studies to examine the mutants that lack this protein C. molecular analyses to identify the interacting partners of this protein D. All of above.
D. All of above.
50. 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. What could be a strategy for drug designing? A. Designing a compound that can compete with the substrate binding to this enzyme. B. Designing a compound that mimic the structure of the ligand that binds to this enzyme. C. Designing a compound that can bind to the ligand and prevent its binding to this enzyme. D. All of above.
D. All of above.
14. Which of the following statements about antibodies is TRUE? A. Antibodies adapt different overall shapes so that they can bind to different antigens. B. Each antibody is composed of two polypeptide chains. C. α helices establish domains in the polypeptide chains. D. Disulfide bonds connect the subunits.
D. Disulfide bonds connect the subunits.
20. Which of the following statements is TRUE? A. Nucleosomes are present in both eukaryotic chromosomes and prokaryotic chromosomes. B. In living cells, chromatin only adopts the extended "beads-on-a-string" form. C. Nucleosomes bind DNA so tightly that they cannot move from the position once assembled. D. Genes that are being transcribed are thought to be in a less condensed chromatin.
D. Genes that are being transcribed are thought to be in a less condensed chromatin.
10. Which of the following statements is TRUE? A. Ionic bonds are strong bonds that make molecules un-soluble in water. B. All hydrophilic molecule form hydrogen bonds with water molecules. C. Hydrophobic interactions are most likely to occur on the surface of a water-soluble protein. D. Phospholipids have both hydrophilic and hydrophobic components.
D. Phospholipids have both hydrophilic and hydrophobic components.
35. 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 the insertion may be removed during mRNA splicing. B. No change in the protein sequence as it could be a nonsense mutation. 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.
16. Which of the following statements about the differences between DNA and RNA is TRUE? A. DNA and RNA have the same backbone, only one of four bases is different. B. DNA can form double helix while RNA cannot. C. Genetic code can be transferred from DNA to RNA, but cannot be transferred from RNA to DNA. D. Unlike the unique function of DNA, RNAs can serve as messenger, structural, or regulatory molecules.
D. Unlike the unique function of DNA, RNAs can serve as messenger, structural, or regulatory molecules.
15. Mutation of a gene leads to a protein that does not function normally, which leads to human diseases. What level(s) of protein structure could be affected by this mutation? A. secondary B. tertiary C. quaternary D. all of above
D. all of above
39. Which of the following mechanisms can retain after cell division? A. histone modification B. DNA methylation C. prion D. all of above
D. all of above
41. Interaction with another protein could a transcription factor. A. activate B. inhibit C. relocate D. all of above
D. all of above
47. To clone a gene into vector, the DNA fragment containing this gene can be isolated from. A. PCR B. genomic DNA library C. cDNA library D. all of above
D. all of above
32. Which of the following histone modifications could be found at activated gene regions? A. acetylation B. phosphorylation C. methylation D. all off above
D. all off above
6. Which microscope can NOT be used to look at the subcellular localization of single ribosomes (30nm). A. TEM B. PALM C. SEM D. fluorescence microscope
D. fluorescence microscope
42. Proteins that are tagged with poly-Ubwill be delivered to . A. spliceosome B. ribosome C. lysosome D. proteasome
D. proteasome
In DNA replication the lagging strand is synthesized discontinuously at the replication fork because DNA polymerase removes the last few nucleotides synthesized whenever it stops. DNA polymerase always falls off the template DNA every ten nucleotides or so. DNA polymerase can polymerize nucleotides only in the 5'-to-3' direction. DNA polymerase needs RNA primer to start DNA synthesis.
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? ER → Golgi → secretory vesicle → outside of the cell nucleus → ER → Golgi → secretory vesicle → outside of the cell ER → Golgi → endosome → outside of the cell Golgi → ER → secretory vesicle → outside of the cell
ER → Golgi → secretory vesicle → outside of the cell
Which of the following statements is TRUE? Extracellular signal molecules that are hydrophilic must bind to a cell-surface receptor so as to signal a target cell. To function, all extracellular signal molecules must be transported by their receptor across the plasma membrane into the cytosol. A receptor bound by only one type of signal molecule can mediate only one kind of cell response.
Extracellular signal molecules that are hydrophilic must bind to a cell-surface receptor so as to signal a target cell.
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 II-I-IV-III II-IV-III-I I-II-III-IV II-IV-I-III
II-IV-I-III
Which of the following statements is TRUE? In anaphase A, chromosome movement is driven by shorten of aster microtubules. Anaphase A is driven by motor proteins kinesin and dynein. In anaphase A, both kinetochore and interpolar microtubules shorten. In anaphase B, microtubules associated with the cell cortex shorten.
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? Influx of Ca2+ into cytoplasm. Nucleation of new actin filaments. Myosin-mediated contraction at the rear of the moving cell. Integrin association with the extracellular environment.
Influx of Ca2+ into cytoplasm.
Which of the following is FALSE of the sodium-potassium pump? It creates an electrochemical gradient across the cell membrane. It transports 2 sodium ions out of the cell and 3 potassium ions into the cell each time. It has enzyme activity to catalyze hydrolysis of ATP to ADP. The sodium gradient created by the pump is used for glucose absorption in the gut.
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? Many human genes are believed to undergo alternative splicing. Most of the human genes contain intron. Most of the human genome code for proteins. Human genome is distributed on 46 chromosomes in most normal cells.
Most of the human genome code for proteins.
Which of the following statement is TRUE? Incorporation of cholesterol increases the fluidity of membrane. Sugars are added to glycolipids at the cytosolic side of Golgi. New phospholipids are synthesized at the cytosolic side of ER. An α-helix containing 20 amino acids must be a transmembrane structure.
New phospholipids are synthesized at the cytosolic side of ER.
A particular strain of yeast produces strains with a mutant cdc2 (M-Cdk) gene, resulting in little to no production of the M-Cdk protein kinase. As a result, what would be expected? These cells will have chromosome condensation. None of these answers. These cells will have the nuclear envelope disperse. These cells will enter M phase.
None of these answers.
Which statement about synapse is TRUE? None of these. Synapse is a specific structure that only mediates signal transduction between neuronal cells. The presynaptic cell and postsynaptic cell are connected by tight junctions. Neurotransmitters are released by the presynaptic cell and absorbed by the postsynaptic cell.
None of these.
Which of the following statements is TRUE? Hydrophobic interactions are most likely to occur on the surface of a water-soluble protein. Water is a polar molecule and hence an excellent solvent for all substances. Phospholipids have both hydrophilic and hydrophobic components. All hydrophilic molecules form hydrogen bonds with water molecules.
Phospholipids have both hydrophilic and hydrophobic components.
Which of the following statements about membrane-enclosed organelles is TRUE? The endomembrane system contains all of the membrane-enclosed organelles. All the membrane-enclosed organelles are surrounded by a double membrane. The membrane of nucleus is always continuous with the membrane of ER. The nucleus is the only organelle that contains DNA.
The membrane of nucleus is always continuous with the membrane of ER.
What will NOT happen if too many misfolded proteins are accumulated in the ER? More chaperon proteins will be produced to correct misfolded proteins. Protein synthesis will be reduced to avoid adding more misfolded proteins. Cell will attempt suicide if the problem can't be solved in time. The misfolded proteins will be packaged and secreted outside to keep the cell healthy.
The misfolded proteins will be packaged and secreted outside to keep the cell healthy.
What would happen if you add a ER-specific signal sequence to the amino-terminal end of a normally cytosolic protein? The ER signal sequence will not be recognized and the protein will remain in the cytosol. The ER signal sequence will be cleaved off and the protein will remain in the cytosol. The protein will be delivered to the ER and fully synthesized in ER. The protein will be fully synthesized in cytosol and then be delivered into the ER.
The protein will be delivered to the ER and fully synthesized in ER.
Which of the following statements about protein transport to mitochondria is TRUE? Proteins are translocated into the mitochondria as completely folded proteins. A protein has to be transported though the outer membrane and the inner membrane separately. The signal that directs a protein to mitochondria is always cleaved off from the final folded protein. All the proteins in mitochondria need to be imported from cytosol.
The signal that directs a protein to mitochondria is always cleaved off from the final folded protein.
Each type of receptor must induce an independent signaling pathway and avoid interference with other intracellular signaling pathways. Which of the following happens when a G-protein-coupled receptor activates a G protein? The β subunit exchanges its bound GDP for GTP. The GDP bound to the α subunit is phosphorylated to form bound GTP. The α subunit exchanges its bound GDP for GTP. It activates the α subunit and inactivates the βγ complex.
The α subunit exchanges its bound GDP for GTP.
Which of the statements below about intermediate filaments is FALSE? They are made of globular subunits. They can be found in the cytoplasm and the nucleus. They can be anchored to the plasma membrane at a cell-cell junction. Each filament is about 10 nm in diameter.
They are made of globular subunits.
Which of the following neurotoxins directly blocks the removal of acetylcholine neurotransmitter? Botulinum Toxin VX Tetrodotoxin Curare
VX
To study a protein that controls development, which of the following model organism may NOT be chosen? Drosophila Arabidopsis Yeast C elegans
Yeast
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? active transport through a channel active transport though a transporter free diffusion passive transport through a transporter
active transport though a transporter
A multipotent cell _________. can give rise to all the tissues and cell types in the body can give rise to some cell types in the body can only give rise to stem cells is considered to be terminally differentiated
can give rise to some cell types in the body
An adult hematopoietic stem cell found in the bone marrow ______________________. will occasionally produce epidermal cells when necessary can produce only red blood cells can produce only white blood cells can undergo self-renewing divisions for the lifetime
can undergo self-renewing divisions for the lifetime
A cell with mutated lamins that cannot be phosphorylated in M phase will be unable to disassemble its nuclear lamina at prometaphase. reassemble its nuclear envelope at telophase. begin to grow microtubules for spindle assembly. condense its chromosomes at prophase.
disassemble its nuclear lamina at prometaphase.
In a benign tumor we may found the following defected programs except ________. enhanced cell migration misregulated cell cycle suppressed apoptosis excessive cell growth
enhanced cell migration
Programmed cell death (apoptosis) can occur _______________. only when extrinsic death signals are present only during embryonic development in some normal cells only in unhealthy or abnormal cells
in some normal cells
A malignant tumor is more dangerous than a benign tumor because its cells ________________. invade other tissues cause neighboring normal cells to mutate proliferate faster attack and phagocytose neighboring cells
invade other tissues
You want to design a drug to inhibit neuron transduction in brain. Which of the following protein complexes can NOT be a target? Ca2+ pump voltage-gated Na+ channel mechanical-gated cation channel K+ leak channel
mechanical-gated cation channel
Which of the following proteins can move cargos through an actin filament? myosin dynein filamin kinesin
myosin
Embryonic stem cells are such a powerful possible treatment for disease because they are______. multipotent pluripotent derived from fetuses well understood
pluripotent
When a terminally differentiated cell in an adult body dies, it can typically be replaced in the body by a stock of ________. proliferating precursor cells that are derived from adult stem cells cells more apically located than the terminally differentiated cells embryonic stem cells induced pluripotent cells
proliferating precursor cells that are derived from adult stem cells
Which of the following is NOT directly required for the function of synapse? Synaptic vesicle voltage gated Ca2+ channel SNARE proton pump
proton pump
Which type of RNA in the following controls mRNA splicing? rRNA snRNA mRNA tRNA
snRNA
Which of the following molecule has the highest permeability to plasma membrane? water proton steroid hormone Glucose
steroid hormone
Progression through the cell cycle requires a cyclin to bind to a Cdk because _________. the binding of a cyclin to Cdk is required for Cdk enzymatic activity the cyclins are the molecules with the enzymatic activity in the complex without cyclin binding, a cell-cycle checkpoint will be activated cyclin binding inhibits Cdk activity until the appropriate time in the cell cycle
the binding of a cyclin to Cdk is required for Cdk enzymatic activity
3. Which organelle can be found in both animal and plant cells? A. cell wall B. chloroplast C. cytoskeleton D. vacuole
C. cytoskeleton
19. Which gene mutation causes substitution of one amino acid in a protein sequence? A. silent B. nonscence C. missence D. frameshift
C. missence
4. In a muscle cell, which internal organelle would you expect to be particularly abundant? A.lysosome B. rough endoplasmic reticulum C. mitochondria D. peroxisome
C. mitochondria
40. Histone modifications can NOT . A. Directly affect nucleosome packaging B. Serve as docking sites for other regulatory proteins C. re-position nucleosomes using the energy of ATP D. retain after cell division
C. re-position nucleosomes using the energy of ATP
Acetylcholine controls the contraction of skeleton muscle and smooth muscle using different signaling pathways. Which mechanism is shared by these two pathways? Acetylcholine binds to ion-channel receptor Ca2+ release from sarcoplasmic reticulum Ca2+ activates calmodulin Phosphorylation of myosin
Ca2+ release from sarcoplasmic reticulum
