Cellular Processes and Molecular Biology Exam Review, Exams of Nursing

Download Cellular Processes and Molecular Biology Exam Review and more Exams Nursing in PDF only on Docsity! CELLULAR AND MOLECULAR BIOLOGY FINAL EXAM NEWEST ACTUAL EXAM 2024-2025 QUESTIONS AND DETAILED CORRECT ANSWERS | VERIFIED ANSWERS The three dimensional details of a specimen can be collected when using: -(A) The light microscope, -(B) The transmission electron microscope, -(C) Image deconvolution, -(D) Formaldehyde fixatives. Correct Answer (C) Which of the following is the best microscope to use in order to collect two dimensional details of a specimen's interior at very high magnification: -(A) The light microscope, -(B) The confocal microscope, -(C) The transmission electron microscope, -(D) The scanning electron microscope. Correct Answer (C) Specific three dimensional details in a biological specimen's interior can most effectively be evaluated when using: -(A) Brightfield microscopy, -(B) The transmission electron microscope, -(C) The confocal microscope, -(D) The scanning electron microscope. Correct Answer (C) A protein that traversed the nuclear membrane of the cell in an alpha helix would tend to have the following characteristics within the transmembrane segment: -(A) polar side groups -(B) a hydrophobic backbone -(C) non-polar side groups -(D) covalent attachment to surrounding lipid molecules -(E) none of the above Correct Answer (C) A protein composed almost entirely from beta sheets would have the following characteristics: -(A) mostly polar side groups -(B) mostly nonpolar side groups -(C) The individual strands of the sheet held together by ionic bonds between peptide bonds in different strands -(D) A very rigid structure -(E) none of the above Correct Answer (E) What type of interaction will these two amino acid side chains experience? -(A) hydrogen bonds -(B) electrostatic interactions -(C) Van der Waals -(D) hydrophobic force Correct Answer (B) In general, ionic bonds within a folded protein structure can form between atoms of two peptide bonds, between Blood flow in a blood vessel could affect signaling pathways of cells in which of the following manners: -(A) by stimulating the secretion of signaling molecules -(B) by altering the shape of GPCRs -(C) by promoting a conformational shape change of G proteins -(D) all of the above -(E) none of the above Correct Answer (D) Put the following steps regarding GPCR/G-protein signaling in the correct sequence: -(1) The G protein dissociates into an asubunit and a bg complex -(2) A signal molecule binds the GPCR -(3) The GTP binds -(4) The GPCR undergoes a conformational shape change -(5) The GDP leaves -(A) 1 - 2 - 5 - 3 - 4 -(B) 2 - 1 - 5 - 4 - 3 -(C) 2 - 4 - 5 - 3 - 1 -(D) 2 - 5 - 3 - 4 - 1 -(E) none of the above Correct Answer (C) GDP and GTP are products of gene expression -(A) True -(B) False Correct Answer (B) The molecule depicted below is an example of a multi- subunit protein -(A) True -(B) False Correct Answer (B) Secondary structure, such as alpha helices and beta sheets, is stabilized primarily by hydrogen bonds involving the polypeptide backbone -(A) True, -(B) False, -(C) Secondary structure is not stable. Correct Answer (A) Which of the following statements is not true: -(A) Regions of the vascular system that branch or curve are more prone to develop disease than the relatively straight regions -(B) A parallel plate flow chamber is designed to expose a smooth surface to a known shear stress -(C) Cells can communicate to each other by secreting water soluble molecules -(D) In vascular disease, endothelial cells are exposed to shear stress yet smooth muscle cells are the primary disease promoting cell type -(E) The addition of conditioned media, as depicted in the third chamber of the schematic, is done to prove that the shear stress stimulus affects smooth muscle cells directly Correct Answer (E) Secondary structure is stabilized primarily by hydrogen bonds between the amino acid side groups -(A) True, -(B) False, -(C) Secondary structure is not stable. Correct Answer (B) G proteins are an example of multi-domain proteins -(A) True -(B) False Correct Answer (B) Protein domain is the term used to describe structurally stable independent regions within one polypeptide chain, which are usually connected to each other by relatively short and unstructured polypeptide segments. -(A) True -(B) False Correct Answer (A) In feedback inhibition, the release of the regulatory molecule from the enzyme's regulatory site serves to activate the enzyme -(A) True -(B) False Correct Answer (A) Collagen is a fibrous extracellular matrix protein that provides resistance to tensile stress: -(A) True -(B) False Correct Answer (A) Elastic fibers are extracellular matrix proteins that provide resistance to tensile stress: -(A) True -(B) False Correct Answer (B) Protein assembly from identical subunits has all the following advantages except one of the following: -(A) Less genetic material is needed In the process shown in the figure below the same phosphate group that is removed from Src in the first step is added back to Src's kinase domain in the last step. -(A) True -(B) False Correct Answer (B) We can infer from the figure that the activating ligand contains a proline-rich peptide sequence and a phosphorylated tyrosine amino acid. -(A) True -(B) False Correct Answer (A) The actions of a protein kinase to modify a protein can be reversed by a: -(A) protein GTPase -(B) protein kinase -(C) protein phosphatase -(D) protein dephosphorylase Correct Answer (C) A diseased coronary artery is conventionally treated in the following manner: (A)With a tissue engineered artery (B)With a stent (C)With an approach that is intended to promote the restenosis of the artery (D)All of the above (E)None of the above Correct Answer (B) Stented arteries often fail due to a process known as instent restenosis: -(A) True -(B) False Correct Answer (A) Which of the following cell component is the cell powerhouse: (A)Endoplasmic Reticulum (B) Golgi Apparatus (C) Mitochondria (D) Plasma Membrane (E) None of the above Correct Answer (C) The selection of drug for the stent coating should be based on which of the following considerations: (A)The ability to load the drug into a polymer coating. (B)The cellular and molecular mechanism of instent restenosis (C)The toxicity of the drug to local cells (D) All of the Above Correct Answer (D) Different cell types within an individual that have a broadly different appearance and function contain different genetic material: -(A) True -(B) False Correct Answer (B) Tissue engineered blood vessel design considerations probably include which of the following: -(A) Mechanical properties; -(B) Biocompatibility; -(C) Cost; -(D) Time to production; -(E) all the above. Correct Answer (E) Which of the following structure is not part of the cell? -(A) lysosomes -(B) extracellular matrix -(C) nucleolus -(D) ribosomes -(E) actin. Correct Answer (B) What would you consider to be the ideal cellular response to the implantation of biomaterial scaffolds for bone regeneration? -(A) The scaffold remains completely inert and avoids interaction with surrounding cells; -(B) surrounding inflammatory cells wall off the scaffold to prevent contamination; -(C) surrounding bone cells migrate into the scaffold and convert the scaffold into normal bone material. Correct Answer (C) Why is cell and molecular biology useful for biomedical engineers? (select the best answer) -(A) It's a nice break from all the math and physics that we have to learn, -(B) Biology is not useful or important, despite what that guy standing up there keeps telling us, -(C) Biology is more interesting than instrumentation, -(D) Many medical devices involve a biological aspect that can be crucial to consider thoughtfully when making decisions related to materials selection and product development. Correct Answer (D) -(C) the extracellular matrix -(D) the ribosomes -(E) all of the above Correct Answer (B) Transcription refers to the conversion of RNA into protein -(A) True -(B) False Correct Answer (B) Proteins, RNA, and DNA are similar in that they are all produced from small precursor molecules. -(A) True -(B) False Correct Answer (A) Up to how many covalent bonds can Carbon form? -(A) 1 -(B) 2 -(C) 3 -(D) 4 -(E) >4 Correct Answer (D) Two molecules in motion within a cell cytoplasm that randomly collide will remain connected together for a period of time that depends upon the number and strength of the non-covalent bonds that form between the two molecules when they collide. -(A) True -(B) False Correct Answer (A) Van der Waals forces are very important for holding together two molecules within a cell that randomly collide. -(A) True -(B) False Correct Answer (B) Carbon is less electronegative than Oxygen. -(A) True -(B) False Correct Answer (A) Which of the following is not true about electrostatic attractions -(A) Attractive forces occur between fully charged groups (ionic bond) and between the partially charged groups of polar molecules -(B) The force of attraction between two partially or fully charged groups falls off rapidly as the distance between the charges increases -(C) In the absence of water, electrostatic forces are strong -(D) Charged groups are shielded by their interactions with water molecules. Electrostatic attractions are therefore quite weak in water -(E) Because they are weakened by water, electrostatic attractions are not very important in biological systems. Correct Answer (E) Which of the following is the strongest type of bond in water: -(A) ionic bond -(B) covalent bond -(C) hydrogen bond -(D) van der waals attraction (per atom) -(E) none of the above Correct Answer (B) Electron microscopes have better resolution due to A)The use of a vacuum B)More accurate lenses C)The small wavelength of an electron D)Higher energies used Correct Answer (C) Protein to protein binding can be impacted by all the following except: -(A) activation energy -(B) protein phosphorylation -(C) protein dephosphorylation -(D) SH2 domains -(E) SH3 domains Correct Answer (A) Because the lipid bilayer is thicker and the lipid composition is specialized in lipid rafts, specific membrane proteins can accumulate there. This enables membrane proteins, which are normally highly mobile, to function together. -(A) True -(B) False Correct Answer (A) In the signaling mechanism shown in the figure, PI-3 kinase causes the two transmembrane receptor proteins to bind together. -(A) True -(B) False Correct Answer (B) When added to cells, detergents surround the amphipathic membrane constituents and displace them from the membrane by disrupting their hydrophobic interactions. Which of the following statement is not true of figure shown: -(A) acetylcholine is produced by the transcription/translation process -(B) the cell surface receptor proteins shown in B, C, and D are products of the transcription/translation process -(C) the intracellular signaling mechanisms activated by acetylcholine in these three cell types are different Correct Answer (A) True (A) or False (B). Signals that lead to altered protein function are much faster than signals that increase protein synthesis, mainly because of the large number of time consuming steps required for protein synthesis. Correct Answer (A) True (A) or False (B). Cells of the same type can respond in different ways to the same signal molecule when the signal molecule is present at different concentrations. Correct Answer (A) True (A) or False (B). Cells can restrict the lateral mobility of specific membrane proteins by use of the underlying cytoskeleton. Correct Answer (A) Would you expect that the ability of a cell to turn the signal on or off would differ significantly between synaptic and endocrine signaling? -(A) Yes -(B) No Correct Answer (A) In the process shown below, where do the calcium ions come from? -(A) Calcium ions are not needed for the process shown because an inorganic phosphate group maintains CaM- kinase II activity. -(B) Ca ions can flow into the cytoplasm when GPCRs activate Gq. -(C) Calcium ions are always present in the cell cytoplasm .-(D) Calcium ions are pre-loaded onto calmodulin and ready whenever they are needed. -(E) None of the above. Correct Answer (B) Which of the following statements is not true (false) regarding the process shown to the right: -(A) Adenylyl cyclase is activated by ATP. -(B) Many copies of cAMP can be made by each adenylyl cyclase enzyme. -(C) cAMP production is an example of a signal amplification. -(D) 5'-AMP is a product of the enzyme cyclic AMP phosphodiesterase. -(E) 5'-AMP can be recycled by the cell into ATP by the addition of two phosphate groups. Correct Answer (A) Which of the following statements is true regarding the signaling pathway shown below: -(A) NO synthase (NOS) is activated in the neuronal cell by acetylcholine. -(B) Arginine activates NO synthase (NOS) to produce NO. -(C) Smooth muscle cell relaxation involves diffusion of cyclic GMP across the cell membrane. -(D) Guanylyl cyclase is the name of the enzyme that produces NO. -(E) none of the above Correct Answer (E) Which of the following statements is true regarding the process shown below: -(A) Once bound by the signal molecule, the plasma membrane receptor undergoes cross (auto) phosphorylation to add phosphate group(s) to random amino acids in the receptor protein. -(B) IRS1 binds to the scaffold protein. -(C) Sos phosphorylates the phosphoinositide docking sites that are used by the proteins in this pathway that have PH domains. -(D) The extracellular signal molecule binds to one receptor protein. -(E) None of the above. Correct Answer (E) Which of the following statements is not true (false) in relation to the process shown below: -(A) Cyclic AMP is generated following activation of the Gi subunit of a G-protein. -(B) Adenylyl cyclase serves to transduce and amplify the signal from the G protein coupled receptor (GPCR). -(C) Many cyclic AMP molecules are produced by each adenylyl cyclase molecule. -(D) The activated PKA molecule is reset to the inactive form of PKA by phosphodiesterase activity. True (A) or False (B): Phosphatidylinositol (PI) is unique among the membrane lipids because it can be phosphorylated at multiple sites. Correct Answer (A) Which of the following statements related to the process shown below is not true: -(A) Apoptosis is inhibited following activation of the apoptosis inhibitory protein. -(B) The "survival signal" is a ligand dimer. -(C) Phosphorylation of Bad leads to its inactivation. -(D) PDK1 and Akt bind together in the cytoplasm and then translocate to the cell membrane as a complex. -(E) When activated, PI 3-kinase can produce the chemical structure recognized by proteins with PH d Correct Answer (D) Which of the following is not true (false) of RNA polymerase: -(A)The enzymes that perform transcription are called RNA polymerases -(B)RNA polymerases catalyze the formation of the phosphodiester bonds that link the nucleotides together to form a linear chain -(C)The RNA polymerase moves along the DNA template, unwinding the DNA helix just ahead of the active site for polymerization -(D)In this way, the RNA chain is extended one nucleotide at a time in the 5'-to-3' direction -(E)One RNA copy can be made from the same gene at any given time, with an additional RNA molecule being started after the first RNA is completed Correct Answer (E) Which of the following is a correct statement regarding the gene promoter: -(A)Signals encoded in RNA dictate where RNA polymerase will start (promoter) and stop (terminator) -(B)A promoter is a special sequence of nucleotides in the DNA indicating the stop point for RNA synthesis -(D)Different promoter sequences bind RNA polymerase with the same degree of strength -(D)None of the above are correct Correct Answer (D) Which of the following is a correct statement regarding RNA processing: -(A)The 3' end of the pre-mRNA is capped as it emerges from the RNA polymerase -(B)Intron sequence removal involves three positions on the RNA:-The 5' splice site-The 3' splice site-The branch point in the intron sequence -(C)Polyadenylation is the mechanism by which most messenger RNA molecules are terminated at their 5' ends. -(D)None of the above Correct Answer (B) Which of the following is not a correct statement regarding protein translation: -(A)The synthesis of proteins is guided by information carried by mRNA molecules -(B)Each nucleotide in mRNA is called a codon -(C)Each codon specifies either one amino acid or a stop to the translation process -(D)A typical eucaryotic cell contains millions of ribosomes in its cytoplasm -(E)All the statements are correct Correct Answer (B) Identify the false statement: -(A)tRNAs are used as adaptors to add each amino acid in the correct sequence until a stop codon is encountered. -(B)The tRNA molecule anticodon forms base pairs with the appropriate codon on the mRNA. This pairing ensures that the correct amino acid is incorporated into the protein chain. -(D)The high energy covalent linkage between the polypeptide and the tRNA is disrupted during each addition. This bond is immediately replaced in the polypeptide chain by the identical linkage on the most recently added amino acid -(D)An aminoacyl-tRNA synthetase couples a specific amino acid to its corresponding tRNA. A different synthetase enzyme for each amino acid ensures that the proper amino acid is attached to its corresponding tRNA. -(E)There are no false statements. Correct Answer (E) Identify the false statement regarding RNA splicing: -(A)Recognition of the three intron positions occur largely through base-pairing between the snRNAs and the consensus RNA sequences in the pre-mRNA substrate. -(B)In the course of splicing, the spliceosome undergoes several shifts in which one set of base-pair interactions is broken and another is formed in its place. -(C)Due to the high specificity of binding, base-pair interactions between the snRNA molecule and the RNA must be completely complementary in order for binding to occur. 6. If the pH of an unknown solution is close to 2, what can you immediately conclude about the solution? A. it is a strong acid B. it is a strong base C. it is a weak acid D. it is a weak base Correct Answer A. it is a strong acid Exam 1 7. Which of the following statements best distinguishes hypotheses from theories in science? A. Theories are hypotheses that have been proved B. Hypotheses are guesses; theories are Correct Answers C. Hypotheses are relatively narrow in scope; theories have broad explanatory power D. Theories are proved true; hypotheses are often contradicted by experimental results Correct Answer C. Hypotheses are relatively narrow in scope; theories have broad explanatory power Exam 1 8. About 25 of the 92 natural elements are known to be essential to life. Four of these 25 elements make up approximately 96% of living matter. Which of the following elements account for most of the remaining 4% of an organism's mass? A. calcium, potassium, phosphorus, sulfur B. oxygen, hydrogen, calcium, nitrogen C. carbon, oxygen, hydrogen, nitrogen D. silicon, hydrogen, nitrogen, arsenic Correct Answer A. calcium, potassium, phosphorus, sulfur Exam 1 9. Which of these best demonstrates unity among organisms? A. descent with modification B. natural selection C. emergent properties D. the structure and function of DNA Correct Answer D. the structure and function of DNA Exam 1 10. Van der Waals interactions can occur when... A. electrons are not symmetrically distributed in a molecule B. molecules held by ionic bonds react with water C. two polar covalent bonds react D. a hydrogen atom loses an electron Correct Answer A. electrons are not symmetrically distributed in a molecule Exam 1 11. The difference between an aldose sugar and a ketose sugar is... A. the ring form and the linear chain B. the number of carbon atoms C. the position of the carbonyl group D. the position of the hydroxyl groups Correct Answer C. the position of the carbonyl group Exam 1 12. You have just sequenced a new protein isolated from mice and observe that sulfur-containing cysteine residues occur at regular intervals. "This finding is most consistent with which of the following claims about the protein? A. Cysteine residues are required for the formation of a helices and ß pleated sheets. B. Cysteine causes bends, or angles, to occur in the tertiary structure of proteins. C. It will be important to include cysteine in the diet of the mice. D. Cysteine residues are involved in disulfide bridges that help form tertiary structure, especially at high temps. Correct Answer D. Cysteine residues are involved in disulfide bridges that help form tertiary structure, especially at high temps. Exam 1 13. The flow of genetic information in a cell goes from... A. protein to RNA to DNA B. DNA to lipid to protein C. DNA to ribosome to RNA D. DNA to RNA to glucose E. DNA to RNA to protein Correct Answer E. DNA to RNA to protein Exam 1 18. Which of the following are compounds? A. H20, 02, and CH4 B. H20 and CH4, but not 02 C. H20 and O2 D. 02 and CH4 Correct Answer B. H20 and CH4, but not 02 A. The membrane is composed of a fluid bilayer of phospholipids with embedded amphipathic proteins. B. The membrane is composed of a mosaic of fluid polysaccharides and amphipathic proteins. C. The membrane is composed of a single layer of fluid phospholipids between two layers of hydrophilic proteins. D. The membrane is composed of a fluid bilayer of phospholipids between two layers of hydrophilic proteins. Correct Answer A. The membrane is composed of a fluid bilayer of phospholipids with embedded amphipathic proteins. Exam 2 2. Which of the following statements best describes the central role that ATP plays in cellular metabolism? A. ATP provides energy coupling between exergonic and endergonic reactions. B. Hydrolysis of ATP provides an input of free energy for exergonic reactions. C. Hydrolysis of the terminal phosphate group from ATP stores free energy that is used for cellular work. D. The terminal phosphate bond is stronger than most covalent bonds in other biological macromolecules. Correct Answer A. ATP provides energy coupling between exergonic and endergonic reactions. Exam 2 3. Which of the following is one of the molecules formed by the removal of a carboxyl group (as CO2) from a molecule of pyruvate? A. water B. citrate C. ATP D. acetyl-CoA Correct Answer D. acetyl-CoA Exam 2 4. What is the name of the barrier that must be overcome before products are formed in a spontaneous (exergonic) reaction? A. entropy B. free energy C. activation energy D. the equilibrium point Correct Answer C. activation energy Exam 2 5. Which of the following molecules make up the majority of the plasma membrane? A. cholesterol B. phospholipids C. proteins D. carbohydrates Correct Answer B. phospholipids Exam 2 7. Which of the following statements best explains why the sodium-potassium pump is an electrogenic pump? A. It decreases the voltage difference across the membrane. B. It is used to drive the transport of glucose against a concentration gradient. C. It generates voltage across the membrane. D. It transports equal quantities of Na+ and K+ across the membrane in opposite directions. Correct Answer C. It generates voltage across the membrane. Exam 2 8. The enzymes that carry out the Electron Transport Chain in eukaryotes are located in.. A. The cytoplasm B. The inner membrane (cristae) C. the intermembrane space D. the matrix of the mitochondrion Correct Answer B. The inner membrane (cristae) Exam 2 6. When chemical, transport, or mechanical work is performed by an organism, what happens to the heat that is generated? A. It is used to power yet more cellular work. B. It is captured to store energy as more ATP. C. it is lost to the environment. D. It is used to generate ADP from nucleotide precursors. Correct Answer C. it is lost to the environment. Exam 9. What kinds of molecules pass through a cell membrane most easily? A. large and hydrophobic B. small and hydrophobic C. ionic D. small and hydrophillic Correct Answer B. small and hydrophobic A. Energy cannot be transferred or transformed B. Energy cannot be created or destroyed C. The entropy of the universe is constant D. The entropy of the universe is decreasing Correct Answer B. Energy cannot be created or destroyed Exam 2 12. Which of the following sequences correctly represents the flow of electrons during photosynthesis? A. H20 → Photosystem I → Photosystem II B. H20 → NADPH → Calvin Cycle C. NADPH →electron transport chain → Oz D. NADPH → 02 → COz Correct Answer B. H20 → NADPH → Calvin Cycle Exam 2 13. Which of the following occurs during the Calvin Cycle? A. carbon fixation B. release of oxygen C. generation of CO2 D. reduction of NADP+ Correct Answer A. carbon fixation Exam 3 1. Meiosis Il is similar to mitosis in that... A. the daughter cells are diploid B. homologous chromosomes synapse C. sister chromatids separate during anaphase D. DNA replicates before the division Correct Answer C. sister chromatids separate during anaphase Exam 3 2. Which of these is a karyotype? A. a display of all of the cell types in an organism B. organized images of a cell's chromosomes C. the appearance of an organism D. a display of a cell's mitotic stages Correct Answer B. organized images of a cell's chromosomes Exam 3. Which of the following sentences state a significant conclusion that Gregor Mendel drew from his experiments with pea plants? A. Genes are composed of DNA. B. Recessive genes occur more frequently in the F1 generation than do dominant ones C. Traits are inherited in discrete units and are not the result of "blending." D. There is considerable genetic variation in garden peas. Correct Answer C. Traits are inherited in discrete units and are not the result of "blending." Exam 3 4. In which stage of the cell cycle is DNA replicated? A. Metaphase B. G2 of Interphase C. Cytokinesis D. S phase of Interphase Correct Answer D. S phase of Interphase Exam 3 5. In some parts of Africa, the frequency of individuals who are heterozygous for the sickle-cell anemia allele is higher than the frequency in North America, presumably because this reduces the frequency of malaria. Such a relationship is related to which of the following? A. Punnett square's modelling inheritance B. Mendel's law of independent assortment C. Mendel's law of segregation D. Darwin's theory of natural selection Correct Answer D. Darwin's theory of natural selection Exam 3 6. What is the greatest benefit of using a testcross to determine an unknown genotype? A. All of the progeny will be heterozygous. B. The homozygous parent is the only one whose crossovers make a difference. C. The homozygous recessive parent is obvious to the naked eye. D. A progeny's phenotype reflects the contribution from the heterozygous parent. Correct Answer D. A progeny's phenotype reflects the contribution from the heterozygous parent. Exam 3 7. Which of the following phenotypes is an example of polygenic inheritance? A. pink flowers in snapdragons B. skin pigmentation in humans C. white and purple flower color in peas D. the ABO blood group in humans Correct Answer B. skin pigmentation in humans B. DNA and proteins C. DNA only D. DNA and phospholipids Correct Answer B. DNA and proteins Exam 3 14. Which of the following conditions is required for a target organ to respond to a particular hormone? A. The target organ must be the same as the organ that produced the hormone. B. The target organ must have receptors that recognize and bind the hormone molecule. C. Cells in the target organ must modify their plasma membranes to allow the hormone to enter the cytoplasm. D. The target organ must have the opposite mating type of the organ that produced the hormone. Correct Answer B. The target organ must have receptors that recognize and bind the hormone molecule. Exam 3 15. Which of the following individuals will inherit an X- linked allele from a male parent who carries the allele? A. all of his daughters B. all of his sons C. half of his daughters D. all of his children Correct Answer A. all of his daughters Exam 3 16. When a neuron responds to a particular neurotransmitter by opening gated ion channels, the neurotransmitter is serving as which part of the signal pathway? A. relay molecule B. signal molecule C. response molecule D. transducer Correct Answer B. signal molecule Exam 3 17. A protein kinase is an enzyme that functions in which of the following ways? A. by adding a phosphate group to activate or inactivate other proteins B. by serving as a second messenger molecule C. by serving as a receptor for various signal molecules D. by activating a G protein Correct Answer A. by adding a phosphate group to activate or inactivate other proteins Exam 3 18. You see a cell dividing under a microscope and a cell plate begins to form across the middle. This cell is most likely... A. a bacterial cell dividing B. a plant cell in metaphase C. a plant cell in cytokinesis D. an animal cell in cytokinesis Correct Answer C. a plant cell in cytokinesis Exam 4 1. A signal peptide... A. Helps target a protein to the ER B. stops translation of messenger RNA C. flags down ubiquitin D. signals the initiation of transcription Correct Answer A. Helps target a protein to the ER Exam 4 2. Which of the following is a reason that the low error rate of DNA replication is important to evolution? A. Replication with a high error rate is likely to kill the cell. B. Rare errors are the source of variation. C. Fixing replication errors provides a cellular role for mismatch repair enzymes. D. Most mutations have no effect on phenotype. Correct Answer B. Rare errors are the source of variation. Exam 4 3. What is the order of Transcription in a eukaryotic cell? A. Termination, elongation, initiation B. Initiation, termination, elongation C. Initiation, elongation, termination D. Elongation, initiation, termination Correct Answer C. Initiation, elongation, termination Exam 4 4. Pick the process that occurs during transcription. A. DNA is replicated B. RNA is synthesized C. proteins are synthesized D. mRNA attaches to ribosomes Correct Answer B. RNA is synthesized Exam 4 A. a deletion of most of the proto-oncogene coding sequence B. a mutation that greatly reduces the stability of a proto- oncogene mRNA C. a mutation that greatly increases the amount of the proto-oncogene protein D. a mutation that blocks transcription of the proto- oncogene Correct Answer C. a mutation that greatly increases the amount of the proto-oncogene protein Exam 4 11. According to the central dogma, what intermediate molecule should go in the blank? DNA →---→Proteins A. cDNA B. rRNA C. mRNA D. tRNA Correct Answer C. mRNA Exam 4 12. At which stage of Interphase does DNA replication occur? A. G1 B. G2 C. G0 D. S Correct Answer D. S Exam 4 13. The release factor (RF) does what action in translation? A. binds to the stop codon in the A site in place of a tRNA and adds a water molecule to break the bond between the polypeptide chain and the last tRNA. B. releases the amino acid from its tRNA to allow the amino acid to form a peptide bond C. supplies a source of energy for termination of translation D. releases the ribosome from the ER to allow polypeptides into the cytosol Correct Answer A. binds to the stop codon in the A site in place of a tRNA and adds a water molecule to break the bond between the polypeptide chain and the last tRNA. Exam 4 14. What are histones? A. the structures that hold two sister chromatids together B. enzymes that elongate the DNA strand during replication C. the sites of origin of DNA replication D. the proteins DNA is wrapped around Correct Answer D. the proteins DNA is wrapped around Exam 4 15. Which of the following is the best way to determine whether alternative splicing of a given gene occurs? A. Isolate the primary transcripts made from the given gene and compare the sequences B. Compare the size of the DNA within the given gene and a similar gene in a related organism C. Compare the sequences of the given gene and a gene known to undergo alternative splicing D. Isolate mRNA from the given gene and compare the sequences Correct Answer D. Isolate mRNA from the given gene and compare the sequences Exam 4 16. What are telomeres? A. the sites of origin of DNA replication B. the ends of linear chromosomes C. enzymes that elongate the DNA strand during replication D. the structures that hold two sister chromatids together Correct Answer B. the ends of linear chromosomes Exam 4 17. DNA methylation and histone acetylation are examples of which of the following processes? A. Translocation B. epigenetic phenomena C. chromosomal rearrangements D. genetic mutation Correct Answer B. epigenetic phenomena Exam 4 18. In wildtype Drosophila embryos, the bicoid mRNA is localized in the anterior part of the embryo. If you inject bicoid mRNA into the embryo's posterior end, which of the following developmental events would occur? A. the embryo would show anterior structures at both ends of the embryo (two-headed embryo) B. the embryo would develop normally C. the embryo would have altered segmentation communites- populations- organisms- organs- tissues- cells- organelles- molecules Exam 1 How do hydrogen bonds differ from covalent bonds? Correct Answer Hydrogen bonds are weaker than covalent bonds Exam 1 What are 4 functions of proteins? Correct Answer providing structure, regulating body processes, transporting molecules, balancing fluids, helps with immunity, and provides energy. Exam 1 List 4 emergent properties of water? Correct Answer - cohesion -expanding while freezing -universal solvent -modulation of temperature Exam 1 Nucleic Acids Correct Answer storage and expression of genomic information Exam 1 Proteins Correct Answer structural support, biochemical catalysts, hormones, enzymes, building blocks, and initiators of cellular death Exam 1 Carbohydrates Correct Answer act as an energy source, helps control blood glucose and insulin metabolism, helps with fermentation Exam 1 Lipids Correct Answer moving and storing energy, absorbing vitamins and making hormones Exam 1 Saturated fats Correct Answer provides energy for the body Exam 1 Unsaturated fats Correct Answer improves blood cholesterol levels Exam 2 Non-competitive enzyme inhibitor Correct Answer enzyme inhibitor characterized by binding to an allosteric site resulting in decreased efficancy of the enzyme. Exam 2 Exocytosis Correct Answer transport of contents to the outside of cell. Exam 2 What happens when electrons gain electrons? Correct Answer reduced Exam 2 What happens when compounds loose electrons? Correct Answer oxidized Exam 2 4 types of junctions between plants or animal cells? Correct Answer -Tight junction- hold two membranes of a cell together (stitches of pants) -Desmosomes- keeps things together strongly (button on pants) -Gap-two communicating (zipper on pants) -Plasmodesmata Exam 2 Autotrophs Correct Answer feed producers, can nourish themselves with CO2 and other inorganic nutrients Exam 2 Heterotrophs Correct Answer humans "receive" Exam 2 Hypotonic Correct Answer cell with swell, popping, more water inside, arrow indicates Turgid Exam 2 Isotonic Correct Answer Cell stays normal, arrow indicates flaccid Exam 2 Hypertonic Correct Answer cell will shrivel up, more water outside, arrow indicates plasmolyzed Exam 3 Diploid cells of the body, such as skin or liver cells. Correct Answer Somatic cells Exam 3 A chromosomal alteration in which the organisms possess more than two complete chromosome sets. Correct Answer Polyploidy Exam 3 Pair of chromosomes of the same length, centromere position, and staining pattern that possess genes for the same characters at corresponding loci. one from father, one from mother. Correct Answer Homologous chromosomes Exam 3 When one gene can affect the expression of another gene (i.e. Labrador dogs) Correct Answer Epistasis Exam 3 What are the 3 stages of signal tranduction in order? Correct Answer 1. Reception, 2. Transduction, 3. Response Exam 3 Describe a family of the receptor signaling pathways and explain and describe how it works and include how the signaling molecule binds the receptor what happens next in signal transduction. Correct Answer Ligand-gated ion channel, like a trash can opening and closing for certain shapes, include ligand, cell membrane, and signal transduction. Exam 3 What apoptosis? Correct Answer programmed cell death Exam 3 XXY is what syndrome? Correct Answer Klinefelter Syndrome- males with reduced fertility; a trisomy Exam 3 X0 is what syndrome? Correct Answer Turner Syndrome- males may be taller and more aggressive Exam 3 XXX is what syndrome? Correct Answer Triple X syndrome Exam 3 Removes a chromosomal fragment resulting in missing genes Correct Answer Deletion Exam 3 Repeats a segment, resulting in an extra copy of certain genes Correct Answer Duplication Exam 3 Reverses a segment within a chromosome, esultingin backwards genes. Correct Answer Inversion Exam 3 Moves a segment from one chromosome to another chromosome. Correct Answer Translocation Exam 3 Goes through cycle only once PMAT, Prophase, Metaphase, Anaphase, Telophase Single division occurs, seperating sister chromatids End results is two diploid cells genetically identical Correct Answer Mitosis Exam 3 Sex Cells Goes through the cycle twice PMAT, Prophase, Metaphase, Anaphase, Telophase Has two times the amount as the other from the two parent cells End result is 4 haploid cells Correct Answer Meiosis 1 & Meiosis 2 Exam 4 Showed that DNA replication is semiconservative Correct Answer Meselson and Stahl Exam 4 Credited with the discovery of the DNA double helix; made DNA model Correct Answer Watson & Crick Exam 4 Took X-ray diffraction pictures of the DNA double-helix that were used by others. Correct Answer Franklin