PCB 3023 Exam 4 - Form A First and Last Name Student ID # (U Number) A Before beginning this exam, please complete the following instructions: 1) Write your name and U number on the first page of this exam. 2) Write AND bubble in your name and U number on the scantron form. Bubble in a ZERO for the letter U. 3) Bubble in your Form on the scantron form. 4) Write in the date in the space provided on the scantron form. Now, complete each section of the exam, carefully reading the instructions first to learn what is required. Feel free to write on this booklet, but remember to encode your final answers on the scantron form. Only answers coded on the scantron will be counted. You may NOT use a calculator for this exam. Good luck!
/ questions: Indicate whether each of the following statements is (A) or (B). CHAPTER 13 1. During glycolysis, many steps in the oxidation process require oxygen. 2. Energy produced during cellular respiration comes from reducing the carbon atoms of glucose. CHAPTER 14 3. The electron-transport chain generates an electrical potential across the membrane because it moves electrons from the intermembrane space into the matrix. 4. Ubiquinone and cytochrome c are both diffusible (mobile) electron carriers. CHAPTER 16 5. The β subunit of a G-protein is lipid-linked to the plasma membrane. 6. IP3 is produced directly by cleavage of inositol phospholipid (PIP2) without the incorporation of an additional phosphate group. 7. Calmodulin directly regulates the intracellular concentration of Ca 2+. 8. Tyrosine phosphorylation serves to build binding sites for other proteins to bind to receptor tyrosine kinases. CHAPTER 17 9. Without actin, cells could form a functional mitotic spindle and pull their chromosomes apart but those cells could not divide. 10. ATP is hydrolyzed by tubulin to cause the bending of flagella. 11. Cells having an intermediate filament network that can NOT be depolymerized would die. 12. The transverse tubules in muscle cells are an extension of the plasma membrane. 2
CHAPTER 18 13. Microtubule polymerization, microtubule depolymerization, and motor proteins are all required for DNA replication during the S phase. 14. During mitosis, microtubules nucleate at the centromere and then connect to a centrosome located at the chromosome s kinetochore. CHAPTER 19 15. Crossing over occurs when two homologous chromosomes form a chiasma. CHAPTER 20 16. Oncogenes can encode for proteins that stimulate cellular growth. MULTIPLE CHOICE. Read the following items carefully and choose the one best response to answer each question or complete each statement. CHAPTER 13 17. Which molecule is acting as the oxidizing agent in the following reaction? C 3 H 5 O 3 + NAD + C 3 H 2 O 3 + NADH + H + a) C3H5O3 b) NAD + c) C3H2O3 d) NADH e) H + 18. Glycolysis occurs in the. a) endoplasmic reticulum b) mitochondrial matrix c) intermembrane space d) cytoplasm e) chloroplast 19. Which of the following is regarding glyceraldehyde 3-phosphate dehydrogenase (G3PD)? a) G3PD catalyzes the oxidization of glyceraldehydes 3-phosphate b) G3PD catalyzes the reduction of NAD + c) G3PD catalyzes the addition of inorganic phosphate in glyceraldehyde 3-phosphate d) Both A and C e) All of the above 3
20. Which of the following is a function of enolase in glycolysis? a) Catalyze the formation of a double bond between two carbon atoms b) Catalyze the formation of ATP c) Catalyze the formation of NADH d) Catalyze the formation of 2-phosphoglycerate e) Catalyze the formation of FADH2 21. Fermentation occurs in cells under anaerobic conditions. Fermentation is coupled with as a mechanism to NADH. a) Citric acid cycle, produce b) Citric acid cycle, reduce c) Citric acid cycle, oxidize d) Glycolysis, oxidize e) Glycolysis, produce 22. A cell is undergoing rapid growth and needs to make a 5 carbon cellular component. Which of the following intermediates of the citric acid cycle (Kreb s cycle) would satisfy the cell s demands? a) citrate b) α-ketogluturate c) succinyl-coa d) isocitrate e) fumarate CHAPTER 14 23. Which of the following is regarding the electron transport chain? a) The redox potential difference between NADH and O2 drives the transport of electrons through the electron transport chain. b) The protein complexes of the electron transport chain are located in the inner membrane. c) Cytochromes consist of colored proteins that contain one or more heme groups. d) Cytochrome oxidase catalyzes the oxidation of oxygen to form water. e) None of the above are true 24. Based on the flow of electrons and protons through the electron transport chain in a cell undergoing active cellular respiration, which of the following is? a) The concentration of H + ions is higher in the mitochondrial matrix as compared to the intermembrane space b) The concentration of NADH is higher in the intermembrane space as compared to the mitochondrial matrix c) ATP is produced in the intermembrane space as H + pass through the ATP synthase d) H + actively enter the intermembrane by transport through the ATP synthase channel e) The ph of the mitochondrial matrix is higher than the ph of the intermembrane space 4
25. The synthesis of ATP during glycolysis occurs via phosphorylation; whereas synthesis of ATP by the ATP synthase occurs via phosphorylation. a) substrate-level, reduction b) substrate-level, oxidative c) oxidative, substrate-level d) substrate-level, photo e) oxidative, oxidative 26. NADH acts a agent on. a) oxidizing, FADH2 b) reducing, cytochrome oxidase c) reducing, NADH dehydrogenase d) oxidizing, NADH dehydrogenase e) oxidizing, cytochrome c CHAPTER 16 27. The end result of the STAT/JAK pathway is... a) the activation of Protein kinase C b) the inhibition of Phospholipase C c) transcription of genes d) translation of PIP e) none of the above 28. Which of the following CORRECTLY illustrates a portion of the phosphorylation cascade leading to release of Bcl2? a) Ras Akt Protein kinase 2 Bad b) Protein kinase 1 + Protein kinase 2 Akt Bad c) PI 3-kinase Akt Protein kinase 2 Bad d) PI 3-kinase Protein kinase 1 Akt Bad e) All of the above could possibly activate Bcl2 29. A researcher exposed mammalian culture to a drug that stimulates an intracellular release of Ca 2+. The drug most likely bound to a and activated. a) Enzyme-linked receptor, Phosphodiesterase C b) Ion channel gated receptor, Phospholipase C c) G protein-coupled receptor, Protein kinase C d) Intracellular receptor, Protein kinase A e) G protein-coupled receptor, Phospholipase C 30. Which of the following are functions of camp? a) Activate protein kinase A b) Activate protein kinase C c) Phosphorylate enzymes d) Phosphorylate gene regulatory proteins 5
e) All of the above 31. A small lipid molecule acting as a signaling molecule is most likely going to bind to which of the following receptors? a) Intracellular receptor b) Paracrine receptor c) Enzyme-linked receptor d) G protein-coupled receptor e) Neuronal receptor 32. A signaling molecule (ligand) binds a G protein-coupled receptor. Shortly afterwards there is an increase in intracellular camp levels. Which of the following has occurred? a) The receptor activated phosphodiesterase which cleaved phosphate from ATP to produce camp b) An activated G-protein activated protein kinase A c) Phospholipase C activated the G protein which lead to an activation of camp d) An activated G-protein activated adenylyl cyclase e) ATP was hydrolyzed by the activated G protein 33. Which of the following statements regarding G protein-coupled receptors is CORRECT? a) The G protein consists of a 7-pass transmembrane protein b) The C-terminus of the receptor is found on the intracellular side of the plasma membrane c) The receptor protein contains 5 stop-transfer sequences d) The G protein is composed of 2 subunits e) All of the above are incorrect 34. Which of the following correctly describes the relationship between a receptor and ligand? a) Receptor and ligand exhibit non-specific bonding b) Receptor and ligand form multiple weak interactions c) Receptor binds more than one ligand at a time d) A ligand can only bind to one type of receptor e) All of the above 35. Activation of enzyme-linked receptors usually involves which of the following? a) Binding of GTP b) Dimerization c) Hydrolysis of ATP d) Hydrolysis of GTP e) Monomeric activation 36. Protein phosphorylation is commonly involved with all of the following EXCEPT: a) regulation of transcription by extracellular signaling molecules b) activation of G protein-coupled receptors c) activation of receptor tyrosine kinase 6
d) activation of MAP kinase kinase kinase CHAPTER 17 37. Which of the following diseases are associated with defects of the intermediate filaments? a) Epidermolysis bullosa b) Progeria c) Sterility d) Both A and B e) Both A and C 38. connect to of adjacent cells to prevent excessive stretching of the cells. a) Intermediate filaments, gap junctions b) Intermediate filaments, desmosomes c) Actin, desmosomes d) Microtubules, gap junctions e) Actin, gap junctions 39. Which of the following would you expect to be associated with actin during the formation of lamellipodium? a) Thymosin b) Profilin c) Gelsolin d) ARP e) Cross-linking proteins 40. Which of the following causes actin filaments to depolymerize? a) Release of GTP b) Release of ATP c) Hydrolysis of ATP d) Hydrolysis of GTP e) Binding of Thymosin 41. The cross-section of a centriole is most similar to a cross section of which of the following? a) Basal body b) Centrosome c) Cilia d) Flagella e) None of the above 42. Which of the following occur when a muscle cell contracts? a) Z discs move further apart b) Actin filaments contract c) Myosin filaments contract 7
d) Myofibrils lengthen e) Sacromeres become shorter CHAPTER 18 43. Which of the following degrades cohesins? a) Securin b) Separase c) Cleavase d) Phosphatase e) S-Cdk 44. During the S phase, DNA is replicated only once. One of the processes that occurs to allow this process includes S-Cdk phosphorylating: a) p53 b) p21 c) Ras d) Cdc6 e) Condensin 45. Dr. Nerdman is a researcher examining the effects of Chemical S on DNA of mice kidney cells. He exposes cells in G1 phase to Chemical S. He suspects the chemical is damaging the DNA. To prove this, which of the following analyses should Dr. Nerdman perform? a) Measure the amount of S-Cdk in the cell b) Measure the amount of DNA in the cell c) Measure the amount of p21 in the cell d) Measure the amount of Cdc6 in the cell e) Measure the amount of Ras protein in the cell 46. The activity of cyclin-dependent kinases is regulated by which of the following? a) Cyclin b) Proteins kinases c) Protein phosphatases d) Both A and B e) All of the above CHAPTER 19 47. A non-disjunction occurring in which phase of the cell cycle would have the most detrimental effect on ALL the gametes produced? a) Prometaphase b) Meiosis I c) Meiosis II d) S phase e) All of the above CHAPTER 20 8
48. White blood cells circulate in the bloodstream and migrate into and out of tissues in performing their normal function of defending the body against infection. Based on your knowledge of a cell, and what we discussed regarding cancer which of the following would be of white blood cells as compared to a normal cell? a) White blood cells would require fewer mutations to become cancerous because they already have genes that allow for invasion of tissues. b) The size of a white blood cell genome would require the cell to undergo more mutations to become cancerous as compared to a normal cell. c) A white blood cell is resistant to cytoplasmic changes and cannot become cancerous. d) Only white blood cells have the capability to metastasize. e) The shape of the white blood cell prevents it from becoming cancerous. 49. Angiogenesis refers to: a) a cell becoming cancerous b) the formation of blood vessels around a tumor c) the formation of a secondary tumor d) the inactivation of the p53 gene e) the activation of receptor tyrosine kinase 50. A mutation causing the protein Ras to be active in the absence of GTP would most likely result in: a) the inactivation of protein kinase A. b) the inactivation of α-subunit. c) the transcription of tumor suppressor genes. d) a cell becoming cancerous. e) the formation of p21 proteins enabling cells to divide uncontrollably 9