BSCI330 Final Exam Review (QUIZZES ONLY)
Which of the following is a function of an IRES? 1. Allows the ribosome to bind to an internal sequence instead of the 5' cap 2. Represses translation by preventing ribosome binding 3. Causes rapid protein degradation by the proteasome 4. Inhibits translation by inactivating initiation factor eIF2
1. Allows the ribosome to bind to an internal sequence instead of the 5' cap
Which of the following is an advantage of a kinase cascade? 1. Amplifies signal during the process of transduction 2. Slows signal transduction to prolong signal 3. uses less energy than a non-cascade pathway 4. none of the above
1. Amplifies signal during the process of transduction
Which of the following organelles is surrounded by a double-membrane (i.e. two complete lipid bilayers) structure? 1. Chloroplast 2. Endoplasmic reticulum 3. Golgi apparatus 4. Ribsome
1. Chloroplast
This type of reaction combines two smaller molecules (such as two amino acids) to form a larger one. 1. Condensation 2. Hydrolysis 3. Proteolysis 4. Isomerization
1. Condensation
Which of the following is NOT a feature of G-protein-coupled receptor mediated signaling? 1. GPCRs bind to hydrophobic ligands and translocate to the nucleus 2. GPCRs contain transmembrane domains 3. Ligand binding on GPCRs causes exchange of GDP for GTP in trimeric G-proteins 4. Cyclic AMP may serve as a second messenger downstream of GPCRs
1. GPCRs bind to hydrophobic ligands and translocate to the nucleus
Which of the following is a role for v-SNARE? 1. Interacts with t-SNARE on target membrane to initiate vesicle fusion 2. Interacts with t-SNARE on vesicle to initiate fusion with target membrane 3. Interacts with t-SNARE on plasma membrane to initiate endocytosis 4. all of the above
1. Interacts with t-SNARE on target membrane to initiate vesicle fusion
Which of the following statements about nuclear pores is TRUE? 1. Ions and small molecules can diffuse freely through the pores, but larger molecules require active transport mechanisms to pass through the pores 2. The pores allow unrestricted access to all molecules, large and small 3. The pores are used to import substances into the nucleus, but the export of materials out of the nucleus uses a different mechanism 4. Nuclear pores open and close in response to changes in voltage across the nuclear membrane
1. Ions and small molecules can diffuse freely through the pores, but larger molecules require active transport mechanisms to pass through the pores
Which of the following is NOT true about an ER signal sequence? 1. It forms an amphipathic alpha helix 2. It contains at least 8 non-polar amino acids in a row 3. It is generally at the N-terminus of the protein 4. It is recognized by the SRP
1. It forms an amphipathic alpha helix
Which of the following receptors is involved in retrograde transport from the Golgi to the ER? 1. KDEL receptor 2. Mannose 6-phosphate receptor 3. PIP 3 receptor 4. all of the above 5. none of the above
1. KDEL receptor
Which of the following is true of photosynthesis? 1. Light reactions lead to the production of ATP and NADPH 2. Dark reactions can only occur in the absence of light 3. Dark reactions use ATP and NADPH to "fix" nitrogen from the atmosphere 4. The reactions all occur in the thylakoid space 5. all the above 6. none of the above
1. Light reactions lead to the production of ATP and NADPH
Which of the following is the LEAST condensed form of DNA? 1. Nucleosome 2. Mitotic Chromosome 3. 30 nm fiber 4. Heterochromatin
1. Nucleosome
Which of the following is a possible property of a prokaryotic cell? 1. Proteins are synthesized by ribosomes 2. Proteins are sorted to different cellular locations by the Golgi apparatus 3. cellular metabolism occurs in the mitochondria 4. all of the above
1. Proteins are synthesized by ribosomes
Which of the following is NOT required for export of a protein from the nucleus to the cytosol? 1. Ran-GDP 2. nuclear export receptor 3. Ran-GTP 4. none of the above
1. Ran-GDP
What is the function of the nucleolus? 1. Ribosome Assembly 2. Protein Translation 3. Initiation of Dna replication 4. Regulation of transport into and out of the nucleus
1. Ribosome Assembly
Which of the following accurately describes how signaling molecules act in autocrine signaling? 1. Signaling molecule acts on the same cell that secreted it 2. Signaling molecule acts on neighboring cells 3. Signaling molecule enters the bloodstream and acts on distant cells 4. none of the above
1. Signaling molecule acts on the same cell that secreted it
Activation of the Rho GTPase leads to bundling of actin microfilaments into a structure called: 1. Stress fibers 2. microfibers 3. microspikes 4. pseudofilaments
1. Stress fibers
Which of the following will occur when an enzyme binds a competitive inhibitor? 1. The Kd will increase but Vmax will not change 2. The Vmax will decrease but Kd will not change 3. Kd will increase and Vmax will decrease 4.There is not enough information to determine
1. The Kd will increase but Vmax will not change
Which of the following statements about cytoskeletal proteins is FALSE? 1. The cytoskeleton is essentially static and does not change over the lifetime of a cell 2. The cytoskeleton provides structural support to the cell and its internal components 3. Cytoskeletal proteins like actin and tubulin are highly conserved over evolution 4. all the above 5. none of the above
1. The cytoskeleton is essentially static and does not change over the lifetime of a cell
Which of the following statements about the plasma membrane of animal cells is TRUE? 1. There is the asymmetric distribution of phospholipids between the inner and outer leaflets 2. The membrane is supported by a cellulose meshwork 3. Sphingolipids are the most abundant type of lipids in the membrane 4. There is little or no lateral diffusion of lipids within a leaflet of the membrane 5. All of the above are true
1. There is asymmetric distribution of phospholipids between the inner and outer leaflets
How are the monomer subunits of cytoskeletal proteins held together to form long fibers? 1. They are held together by non-covalent interactions 2. they are held together by disulfide bonds 3. They are held together by a combination of non-covalent and disulfide bonds 4.none of the above
1. They are held together by non-covalent interactions
Which of the following is true of kinesins? 1. They move from minus end to plus end on microtubules 2. They move from minus end to plus end on microfilaments 3. They move from plus end to minus end on microtubules 4. They move from plus end to minus end on microfilaments
1. They move from minus end to plus end on microtubules
Which of the following is the location of an electron transport chain? 1. Thylakoid membrane 2. Outer mitochondrial membrane 3. Mitochondrial matrix 4. Chloroplast stroma 5. all the above
1. Thylakoid membrane
The addition of nucleotides by DNA polymerase during DNA synthesis requires a primer. 1. True 2. False
1. True
True or False: You can create a whole sheep from the nucleus of one of its skin cells by combining that nucleus with an egg cell without a nucleus. 1. True 2. False
1. True
A protein domain that is found in many related proteins is called a(n) 1. motif 2. exon 3. secondary structure 4. none of the above
1. motif
When miRNA or siRNA associate with the Argonaute proteins, which complex is generated? 1. slicer 2. dicer 3. ricer 4. splicer
1. slicer
Which of the following does NOT accurately describe riboswitches: 1. their function is enhanced by DNA polymerase 2. They are particularly common in bacteria 3. They are often located near the 5' end of mRNAs 4. They change their conformation upon binding small molecules
1. their function is enhanced by DNA polymerase
True or False: Formation of the mitotic spindle is essential for chromosome segregation in eukaryotic cells. 1. true 2. false
1. true
True/False - Even in the absence of any harmful agents, the longer we live the greater our chance of getting cancer. 1. true 2. false
1. true
Which of the following statements about the genetic code is FALSE? 1. AUG, the start codon, codes for methionine 2. A three-base codon system contains 24 possible codons 3. Multiple codons can encode for the same amino acid 4. stop codons do not code for amino acids
2. A three-base codon system contains 24 possible codons
The second messenger inositol trisphosphate (IP3) causes calcium ions to: 1. Be pumped from the cytosol to the ER 2. Be released from the ER 3. be secreted from the cel 4. none of the above
2. Be released from the ER
Steroid hormones: 1. Signal via G-protein-coupled receptors 2. Bind cytosolic receptors and induce nuclear translocation 3. Are hydrophilic molecules that cannot cross the plasma membrane 4. all the above
2. Bind cytosolic receptors and induce nuclear translocation
Which of the following is NOT a common feature of glucose oxidation and photosynthesis? 1. Both use proton gradients to generate ATP 2. Both involve the reduction of NAD+ to NADH 3. Both utilize electron transport chains 4.Both use metabolic cycles 5. None of the above (i.e. all are common to both processes)
2. Both involve the reduction of NAD+ to NADH
Which of the following molecules CANNOT simply diffuse across a lipid bilayer? 1. O2 2. Chloride ions 3. Cortisol 4. CO2
2. Chloride ions
At what point in photosynthesis is water split? 1. During the light reactions, as the final electron acceptor for the first electron transport chain 2. During the light reactions, to replace the electrons lost by Photosystem II 3. During the dark reactions, to fix carbon dioxide 4. During the dark reactions, to oxidize NADPH
2. During the light reactions, to replace the electrons lost by Photosystem II
Which of the following is true of enzyme catalysis? 1. Enzymes speed up reactions by decreasing the free energy of the products 2. Enzymes speed up reactions by decreasing the activation energy 3. Enzymes speed up reactions by destabilizing the intermediate states 4. all the above
2. Enzymes speed up reactions by decreasing the activation energy
The 5' UTR, but NOT the 3' UTR, may be involved in regulating translation. 1. True 2. False
2. False
The semiconservative nature of DNA replication means that some parts of a DNA molecule are replicated and other parts are not. 1. True 2. False
2. False
True or False: Most gene regulatory proteins make contacts with the minor groove of DNA. 1. True 2. False
2. False
True or false: Glycolysis occurs in mitochondria 1. True 2. False
2. False
This component of the plant cell wall forms a gel that provides resistance to compression. 1. Cellulose 2. Pectin 3. Lignin 4. Remodeling enzymes 5. none of the above
2. Pectin
This class of covalent bond links two nucleotides in a nucleic acid 1. Glycosidic bond 2. Phosphodiester bond 3. peptide bond 4. nucleotic bond 5. peptide bond
2. Phosphodiester bond
A question on beer: Which of the following is true about the production of alcohol by fermentation? 1. Glucose is converted to glycogen 2. Pyruvate is converted to ethanol 3. A net of 4 ATP is produced per glucose molecule 4.It only occurs in the presence of oxygen 5. all of the above
2. Pyruvate is converted to ethanol
Which of the following is NOT a role for actin-myosin complexes? 1. Contractile ring in cytokinesis 2. Separation of chromosomes in mitosis 3. Muscle contraction 4. Movement of vesicles in the cytoplasm 5. none of the above (all are function)
2. Separation of chromosomes in mitosis
Which of the following is TRUE about DNA replication? 1. The lagging strand is synthesized as one continuous strand 2. The DNA helicase is loaded on the lagging strand template 3. Okazaki fragments are synthesized on the leading strand 4. Loading of the sliding clamp on DNA does not require ATP
2. The DNA helicase is loaded on the lagging strand template
Polarized cells have defined apical and basolateral surfaces. Which type of junction prevents diffusion of proteins between these surfaces? 1. Desmosomes 2. Tight junctions 3. Gap junctions 4. None of the above
2. Tight junctions
Which of the following is an example of transmembrane transport? 1. Transport of a protein from the cytosol to the nucleus 2. Transport of a protein from the cytosol to the ER 3. Transport of a protein from the Golgi apparatus to the endosomes 4. Transport of a protein from the ER to the Golgi apparatus 5. all of the above
2. Transport of a protein from the cytosol to the ER
Antiporters are transporters that move: 1. Two different substances in the same direction 2. Two different substances in opposite directions 3. A single substance against its concentration gradient 4. A single substance down its concentration gradient
2. Two different substances in opposite directions
Which of the following describes an allosteric regulator? 1. Aspirin inhibits the enzyme COX-2 by covalently binding to the active site 2. cAMP activates protein kinase A by binding to a regulatory site distinct from the active site 3. Cyanide inhibits cytochrome oxidase by binding to the active site 4. all the above 5. none of the above
2. cAMP activates protein kinase A by binding to a regulatory site distinct from the active site
Which class of enzymes covalently add phosphate groups to proteins? 1. Phosphatases 2. kinase 3. Phosphorylases 4. Tyrosinases
2. kinase
DNA-only transposons require which enzyme(s) to move from one location to another? 1. integrase 2. transposase 3. DNA polymerase 4. all the above
2. transposase
Which of the following occurs when an enzyme binds a non-competitive inhibitor? 1. The Kd will increase but Vmax will not change 2. The Vmax will decrease but Kd will not change 3. Kd will increase and Vmax will decrease 4. There is not enough information
2.The Vmax will decrease but Kd will not change
Which of the following is a property of RNA splicing? 1. splicing occurs in the cytosol after RNA is exported from the nucleus 2. An RNA transcript can only be spliced in one way by any given cell type 3. Alternative splicing can generate different protein sequences from the same original RNA sequence 4. Most prokaryotic genes have introns that must be spliced out 5. none of the above
3. Alternative splicing can generate different protein sequences from the same original RNA sequence
How are molecular pump proteins able to generate directional motion, when protein shape changes are reversible? 1. By only moving substrates down a concentration gradient 2. By always moving one substrate in one direction, and a second substrate in the opposite direction 3. By coupling shape changes to ATP hydrolysis 4. None of the above
3. By coupling shape changes to ATP hydrolysis
Which of the following statements about enzymes is FALSE 1. Enzymes do not change the ∆G for a chemical reaction 2. Enzymes cannot change the equilibrium ratio of reactants and products 3. Enzymes can convert a non-spontaneous reaction to a spontaneous reaction 4. all of the above 5. none of the above
3. Enzymes can convert a non-spontaneous reaction to a spontaneous reaction
DNA in the nucleus is packaged as chromatin. Which of the following statements about chromatin is FALSE? 1. The basic unit of chromatin, the nucleosome, contains DNA wrapped around a histone octamer core 2. The nuclear lamina serves as a scaffold for higher-order chromatin structure 3. Euchromatin contains DNA sequences that are not expressed, including the centromeres. 4. Chromatin is a dynamic structure, which can condense and open as needed by the cell
3. Euchromatin contains DNA sequences that are not expressed, including the centromeres.
What is the role of molecular oxygen during glucose metabolism? 1. Oxidation of glyceraldehyde 3-phosphate to generate NADH 2. Oxidation of pyruvate to generate acetyl CoA 3. Final electron acceptor for the electron transport chain 4. All the above
3. Final electron acceptor for the electron transport chain
Which of the following is NOT an example of substrate-level phosphorylation? 1. Generation of ATP during glycolysis 2. Generation of GTP during the citric acid cycle 3. Generation of ATP by ATP synthase via chemiosmosis 4. None of the above (i.e. all are substrate-level phosphorylation)
3. Generation of ATP by ATP synthase via chemiosmosis
The secondary structure of a protein is held together by which of the following? 1. Non-covalent interactions between R-groups 2. Peptide bonds between amino acids 3. Hydrogen bonds between carbonyl and amine groups in the peptide backbone 4. Disulfide bonds
3. Hydrogen bonds between carbonyl and amine groups in the peptide backbone
Which of the following is NOT true about protein folding? 1. It occurs spontaneously 2. It results in the lowest energy state for the protein 3. It always requires an input of energy 4. It sometimes requires assistance from a chaperone protein
3. It always requires an input of energy
Which of the following statements about turgor pressure is FALSE? 1. It is highest when the extracellular environment is hypotonic 2. It relies on the osmosis of water into the cell 3. It provides rigidity to animal cells 4. none of the above
3. It provides rigidity to animal cells
Which of the following adhesion molecules is independent of calcium ions? 1. E-cadherin 2. L-selectin 3. LFA-1 (an integrin) 4. all of the above 5. none of the above
3. LFA-1 (an integrin)
Which of the following is TRUE about zinc finger proteins? 1. All zinc finger proteins recognize the same DNA sequence. 2. Some zinc finger proteins do not coordinate a zinc ion. 3. Multiple zinc finger domains can be strung together to recognize a long sequence. 4. Zinc finger proteins generally bind carbohydrates.
3. Multiple zinc finger domains can be strung together to recognize a long sequence.
What kind of feedback loop ensures robust start of events during the cell cycle. 1. Circular 2. Negative 3. Positive 4. none of the above
3. Positive
Which of the following is NOT a consequence of the domain structure of proteins? 1. Proteins may contain multiple independently functioning parts 2. Proteins are modular in nature 3. Protein structures are rigid and inflexible 4. all the above 5. none of the above
3. Protein structures are rigid and inflexible
Which of the following is NOT a mechanism of epigenetic inheritance? 1. methylation of DNA on CpG sequences 2. Positive feedback loop maintaining expression of a protein 3. Removal of introns during RNA splicing 4. Modification of chromatin structure by acetylation of histones
3. Removal of introns during RNA splicing
Which of these techniques has the HIGHEST level of resolution? 1. Visible light microscopy 2. Fluorescence Microscopy 3. Scanning Electron microscopy 4. Confocal microscopy
3. Scanning Electron microscopy
Which of the following is required for transport of a protein from the cytosol into the mitochondrial matrix? 1. Singal recognition particle 2. COPII 3. TOM 4. Ran
3. TOM
Which of the following is FALSE about signaling molecules? 1. The effect of a signaling molecule depends on the cell type on which it is acting 2. cells typically need signals to stay alive. 3. The concentration of a signaling molecule is not important for the cellular response. 4. There are signaling molecules that can cross cell membranes.Microfibers
3. The concentration of a signaling molecule is not important for the cellular response.
How is a tRNA "charged"? 1. it's covalently attached to AMP 2. it's covalently attached to an aminoacyl-tRNA synthase 3. it's covalently attached to an amino acid 4. all of the above
3. it's covalently attached to an amino acid
Which type of transposon(s) uses an endonuclease-nick mechanism to move? 1. DNA-only transposon 2. retrovirus-like retrotransposon 3. non-retrovirus-like retrotransposon 4. All the above
3. non-retrovirus-like retrotransposon
Which of the following does NOT contribute to reducing the error rate of DNA replication? 1. 5' to 3' replication 2. strand-directed mismatch repair 3. nuclear membrane 4. 3' to 5' exonucleolytic proofreading
3. nuclear membrane
Which of the following does not result from the amphipathic nature of phospholipids? 1. Formation of lipid micelles 2. Formation of lipid bilayers 3. Formation of closed (spherical) membrane structures 4. Ability of charged molecules to readily diffuse through membranes 5. None of the above
4. Ability of charged molecules to readily diffuse through membranes
Which of the following is NOT an advantage of light microscopy over electron microscopy? 1. Ability to visualize in multiple colors 2. Ability to visualize living cells 3. Ability to visualize cells within intact tissue 4. Ability to determine the structure of macromolecular complexes
4. Ability to determine the structure of macromolecular complexes
Which of the following accurately describes how a cell can control the proteins it makes? 1. RNA processing 2. transcriptional 3. protein activity 4. All of the above
4. All of the above
Which of the following is true about the process of translation? 1. GTP is hydrolyzed at several important steps 2. The catalytic component of the ribosome is composed of RNA 3. the translation initiation complex contains a special initiator tRNA 4. All of the above 5. none of the above
4. All of the above
Which of the following statements about the nuclear membrane is TRUE? 1. It is supported by the meshwork of the nuclear lamina 2. It is continuous with the endoplamic reticulum 3. It has a double-membrane (two lipid bilayers) structure 4. All of the above 5. None of the above
4. All of the above
Which of the following is a property of metabolic cycles (such as the citric acid cycle)? 1. Allow multiple points of regulation 2. Allow multiple points of regulation 3. Generate new biomolecules that can be used by the cell 4. All the above
4. All the above
Which of the following is frequently mutated in cancer? 1. Ras 2. LacZ 3. Rb (Retinoblastoma) 4. Both 1 and 3
4. Both 1 and 3
Which of the following is NOT a carbohydrate polymer? 1. Cellulose 2. Glycogen 3. Chitin 4. Phosphatidylcholine 5. none of the above (all are carbohydrate polymers)
4. Phosphatidylcholine
Which of the following is involved in the siRNA pathway but NOT the microRNA pathway? 1. Slicer 2. Dicer 3. RISC 4. RITS complex
4. RITS complex
Which of the following models describes the structure of the plasma membrane? 1. the endosymbiotic theory 2. The induced fit model 3. the central dogma 4. The fluid mosaic model
4. The fluid mosaic model
Which of the following statements about ribosomes is TRUE? 1. Ribosomes are surrounded by the ribosomal membrane 2. Bacterial ribosomes are larger and more complex than eukaryotic ribosomes 3. Ribosomes synthesize cytoplasmic proteins, but not secreted proteins 4. The individual ribosome subunits are assembled in the nucleolus, a substructure of the nucleus 5. none of the above
4. The individual ribosome subunits are assembled in the nucleolus, a substructure of the nucleus
Metastasis is a particularly difficult problem to tackle in cancers. Which of the following is NOT a characteristic of cancer metastases? 1. They can be detected using the fact that cancer cells consume more glucose than other cells in the vicinity. 2. Cells that metastasize use extracellular proteases to cut through the extracellular matrix as they move from one place to another. 3. They can move long distances through capillaries. 4. They always move to pre-designated places inside an organism.
4. They always move to pre-designated places inside an organism.
Which is TRUE about both retroviral-like retrotransposons and nonretroviral retrotransposons? 1. They both have long terminal repeats (LTRs). 2. They both require integrase for movement. 3.They both move as DNA. 4. They both require reverse transcriptase for movement.
4. They both require reverse transcriptase for movement.
An allosteric regulator of an enzyme 1. Binds to a site away from the active site 2. causes a shape change in the enzyme that affects enzyme function 3. Binds non-covalently to an enzyme 4. all of the above 5. none of the above
4. all of the above
Regulation at the drosophila 'Eve' gene exemplifies complex control regions that: 1. Can be found in plants and animals 2. Can respond to many different inputs, and integrate this information 3. Can produce a complex spatial and temporal output as development proceeds 4. all of the above
4. all of the above
Which of the following compartments is topologically similar to the ER? 1. golgi apparatus 2. lysosomes 3. exterior of the cell 4. all of the above 5. none of the above
4. all of the above
Which of the following is a feature of regulated secretion? 1. Concentration of cargo in a specialize vesicle 2. vesicle fusion with plasma membraane 3. Secretion depends on signals from outside the cell 4. all of the above 5. none of the above
4. all of the above
Which of the following is a function of the 5' methylguanosine cap? 1. Protect the 5' end of the RNA from degradation in the cytosol 2. Serve as a binding site for the ribosome 3. Interact with the 3' poly-A tail to enhance translation 4. all of the above
4. all of the above
Which of the following is a property of the inner mitochondrial membrane? 1. It is folded into cristae 2. it's rich in the universal lipid cardiolipin 3. contained the electron transport chain 4. all of the above 5. none of the above
4. all of the above
Which of the following contributes to the affinity of protein binding to a ligand? 1. Charge-charge interactions 2. Having multiple contacts 3. Having complementary shapes 4. all the above
4. all the above
Which of the following is a function of molecular tunnels in enzymes? 1. Helps prevent intermediate products from diffusing away 2. Prevents reactive intermediates from interacting with the aqueous environment 3. Ensures that multi-step reactions occur in the correct order 4. all the above 5. none of the above
4. all the above
Which of the following is a major regulatory transition or checkpoint that occurs during the cell cycle? 1. Metaphase to anaphase transition 2. G2/M checkpoint 3. Start checkpoint 4. all the above
4. all the above
Which of the following is a potential outcome of homologous recombination? 1. Repair broken replication forks 2. Repair double-strand breaks 3. Cause chromosomal crossovers 4. all the above 5. none of the above
4. all the above
Which of the following may be a result of transposon activity? 1. Corn kernel color variegation 2. Spreading of bacterial antibiotic resistance 3. F1 hybrid sterility in fruit flies 4. all the above 5. none of the above
4. all the above
Which of the following metabolic steps requires the expenditure of energy? 1. Activating glucose by phosphorylation 2. Transporting pyruvate from the cytosol into the mitochondrion 3. Fixing carbon in the Calvin cycle 4. all the above
4. all the above
Which of the following kinds of mitotic microtubules bind to identical substrates at their plus ends? 1. Astral microtubules and kinetochore microtubules 2. interpolar microtubules and astral microtubules 3. Kinetochore microtubules and interpolar microtubules 4. none of the above
4. none of the above
Which of the following statements about actin monomers is TRUE? 1. actin monomers bind GTP 2. Actin monomers are composed of alpha and beta actin 3. Actin monomers are known as F actin 4. all the above 5. none of the above
5. none of the above
Which of the following is NOT a function of the Golgi apparatus? 1. Modification of N-linked glycosylation on proteins 2. Attachment of O-linked glycosylation to proteins 3. Synthesis of carbohydrates 4. Sorting of proteins to other organelles 5. all the above 6. none of the above
6. none of the above
