Bio 101 Section 001: Practice Questions for First Exam

Transcription

1 Do the Practice Exam under exam conditions. Time yourself! MULTIPLE CHOICE: 1. The substrate fits in the of an enzyme: (A) allosteric site (B) active site (C) reaction groove (D) Golgi body (E) inhibitor site 2. Cofactors are: (A) non-protein molecules that aid enzyme catalysis. (B) protein molecules that aid enzyme catalysis. (C) enzyme inhibitors. (D) enzyme substrates. Bio 101 Section 001: Practice Questions for First Exam 3. When the rate of enzyme catalysis is plotted against temperature, the curve rises slowly at low temperatures because: (A) the enzymes are denatured. (B) this is the optimal temperature for enzyme catalysis. (C) the enzyme is inhibited. (D) the substrates do not move as fast at lower temperatures. 4. Enzymes speed up reaction rates because: (A) they supply the activation energy. (B) they provide heat. (C) they lower the activation energy. (D) they increase the activation energy. 5. ATP is used to fuel: (A) exergonic reactions. (B) endergonic reactions. (C) diffusion. (D) movement of water across the cell membrane. (E) all of the above. 6. Which of the following is not a part of the ATP molecule: (A) adenine. (B) ribose sugar. (C) deoxyribose sugar. (D) phosphate. (E) A and B. 7. ATP is usually recycled from: (A) DNA. (B) AMP and inorganic phosphate. (C) ADP and inorganic phosphate. (D) AQP. (E) None of the above, it is always made directly from sugar, base, and phosphate. 1

2 8. Photosynthesis can be broken down into 2 principle stages, which are: (A) the light reactions and Krebs cycle. (B) glycolysis and the Calvin cycle. (C) electron transport in the chloroplasts and in the mitochondria. (D) the light reactions and the Calvin cycle. 9. Plants are examples of: (A) autotrophic organisms. (B) heterotrophic organisms. (C) photoautotrophic organisms. (D) photosynthetic organisms. (E) A, C, and D. 10. Leaves of deciduous trees turn red, orange, and yellow in fall because: (A) frost damages cholorohyll. (B) chlorophyll is no longer manufactured. (C) the carotenoid pigments are no longer masked. (D) carotenoids are no longer manufactured. 11. Even if catalysts are available, must also be present for a reaction to occur. (A) energy (B) water (C) cofactors (D) heat (E) All of the above. 12. Which of the following are examples of electron carriers that are used in photosynthesis? (A) NAD +. (B) NADP +. (C) FADH 2. (D) A and C. (E) All of the above. 13. Photosynthesis occurs in: (A) leaves. (B) roots. (C) the cell wall. (D) mitochondria and chloroplasts. (E) A and D. 14. Oxygen is produced during photosynthesis when: (A) water molecules are split to provide electrons for photosystem I. (B) water molecules are split to provide electrons for photosystem II. (C) NADH and FADH 2 donate electrons. (D) NADPH is made. 15. Chlorophylls a and b mainly absorb: (A) violet-blue and red light. (B) green light. (C) blue and green light. (D) orange and yellow light. (E) all of the above. 2

3 16. In the light reactions of photosynthesis, high energy electrons are passed out of the photosystem by: (A) the electron acceptor molecule. (B) the electron donor molecule. (C) carotenoids. (D) specialized chlorophyll a molecules. (E) B and D. 17. In photosynthesis, ATP is made in the: (A) matrix. (B) thylakoid space. (C) stroma. (D) intermembrane space. (E) cytoplam. 18. In the Calvin cycle, carbon atom(s) from molecules of CO 2 is/are added to 3 molecules of a 5 C sugar to make one molecule of glucose and regenerate the starting material so that the cycle can continue. (A) 1,1 (B) 1,3 (C) 3, 3 (D) 6,6 (E) 1,6 19. The energy for life is produced by: (A) aerobic respiration. (B) anaerobic respiration. (C) photosynthesis. (D) sex. 20. The waste products of respiration are used for: (A) photosynthesis. (B) respiration. (C) deforestation. (D) heredity. (E) nucleotide synthesis. 21. The H + are pumped from to in the electron transport chain of photosynthesis: (A) stroma to thylakoid space. (B) thylakoid space to stroma. (C) matrix to intermembrane space. (D) intermembrane space to matrix. (E) None of the above H + are not pumped, they move down their concentration gradient only. 22. Grana is/are: (A) enzymes that function in active transport. (B) found in the chloroplasts. (C) stacks of thylakoids. (D) aging cells. 23. The potential energy that an electron loses as it is passed down the electron transport chain to photosystem I is used to: (A) pump protons into the stroma. (B) pump protons into the thylakoid space. (C) pump hydrogen ions from the stroma to the thylakoid space. (D) synthesize ATP. (E) B, C, and D. 3

4 24. Which of the following is not true? ATP synthase: (A) functions in breaking down ATP into ADP and P i. (B) allows H + to diffuse back to the stroma. (C) is found in the thylakoid membrane. (D) is an enzyme. (E) both A and D. 25. p53 is: (A) a tumor suppressor gene. (B) part of the kinetochore. (C) a structure that forms the spindle fibers. (D) a transmembrane protein. (E) involved in active transport. 26. Gametes: (A) are haploid cells. (B) fuse to form a zygote. (C) are produced by meiosis. (D) all of the above. 27. In prophase I of meiosis: (A) crossing over occurs. (B) chromosomes reach opposite poles of the cell. (C) chromosomes align at the cell equator. (D) the nuclear membrane is reformed. (E) sister chromatids separate. 28. In anaphase I of meiosis: (A) crossing over occurs. (B) the cytoplasm divides. (C) the homologues separate. (D) sister chromatids separate. (E) the centrioles form the spindle fibers. 29. Alternation of generations refers to: (A) the alternation of egg and sperm. (B) the alternation of a haploid and a diploid generation. (C) the presence of 2 sexes. (D) the dependence of one generation on the next. 30. Genetic variation is ensured by: (A) random fertilization. (B) crossing over during meiosis. (C) independent assortment. (D) all of the above. 31. Trisomy is: (A) one chromosome too few. (B) tetraploidy. (C) a type of cancer. (D) a tumor suppressor gene. (E) one chromosome too many. 4

5 32. A benign tumor is: (A) composed of mobile cells that seed new tumors in secondary tissues. (B) malignant. (C) encapsulated and non-invasive. (D) a childhood cancer. 33. The end product of glycolysis is: (A) acetyl-co A. (B) carbon dioxide and water. (C) pyruvate. (D) glucose. (E) oxaloacetate. 34. Krebs cycle occurs in the: (A) cytoplasm. (B) stroma. (C) matrix. (D) thylakoid membrane. (E) inner mitochondrial membrane. 35. The final electron acceptor in aerobic respiration is: (A) water. (B) oxygen. (C) NAD +. (D) FADH 2. (E) glucose. 36. In aerobic respiration carbon dioxide is produced in: (A) gycolysis. (B) Krebs cycle. (C) acetyl-coa production. (D) the electron transport chain. 37. The function of glycolysis is to: (A) produce NADPH and ATP. (B) the starting material for further energy extraction by oxidation. (C) produce glucose. (D) produce NADH and FADH 2. (E) make 36 ATP from one glucose molecule. 38. The net energetic products of Krebs cycle are: (A) 2 ATP and 2 NADH. (B) 2 ATP, 6 NADH, and 2 FADH 2. (C) 2 NADH. (D) 36 ATP. (E) one molecule of glucose and 9 ATP. 39. In respiration, NADH activates proton pumps: (A) 1. (B) 2. (C) 3. (D) 4. (E) 6. 5

6 ATP net, rather than 34 ATP net, are made by the electron transport chain of respiration because: (A) the NADH made by glycolysis has to be transported into the mitochondrial matrix. (B) the NADH made by glycolysis has to be transported into the cytoplasm. (C) the NADH made by Krebs cycle has to be transported into the mitochondrial matrix.. (D) the NADH made by Krebs cycle has to be transported into the cytoplasm. 41. The most efficient process (in the following list) of cellular respiration is: (A) glycolysis. (B) acetyl-coa production. (C) Krebs cycle. (D) Calvin cycle. (E) light reactions. 42. Cancer occurs in humans less frequently than expected because: (A) humans are rarely exposed to carcinogens. (B) human DNA rarely mutates. (C) p53 detects cancers and signals the cell accordingly. (D) ATP checks the cell at certain points in the cell cycle. 43. The pairing of homologues in prophase I of meiosis is called: (A) crossing over. (B) synapsis. (C) gametogenesis. (D) independent assortment. (E) kinetochore. 44. Ploidy is: (A) breakdown of the nucleus in cell division. (B) an attachment between homologues that have crossed over. (C) detachment of the chromosomes from the kinetochore microtubules at the end of mitosis. (D) the number of sets of chromosomes possessed by a cell. 45. Mitosis and meiosis differ in: (A) the number of cell divisions that occurs. (B) the final ploidy of the daughter cells. (C) the number of daughter cells produced. (D) the composition of the spindle fibers. (E) A, B, and C. 46. To ensure true-breeding parental plants Mendel: (A) self fertilized each variety for several generations. (B) crossed 2 varieties with alternate traits. (C) self-fertilized the F 1 generation. (D) A and B. 47. When Mendel crossed 2 varieties of true-breeding plants the F 1 generation were: (A) 100% heterozygous. (B) 100% homozygous. (C) 50% heterozygous. (D) 75% heterozygous. 6

7 48. The degree of earlobe attachment in humans is inherited as a simple dominant of free earlobes, or as a recessive allele of attached earlobes. What is the probability that a woman with attached earlobes will have children with attached earlobes if their father has free earlobes, but his father had attached earlobes? (A) 1 in 2. (B) 3 in 4. (C) 100%. (D) 1 in 10. (E) none. 49. Alleles are: (A) homologous chromosomes. (B) alternate forms of a gene. (C) the appearance of an individual. (D) the genotype of an individual. (E) heterozygous individuals. The following statement is for questions 50 and 51: In a particular breed of cats, black (B) is dominant to white (b). A black heterozygous cat is crossed with a black homozygous cat. 50. The genotypic ratio is: (A) 1:1 homozygous to heterozygous. (B) 3:1 heterozygous to homozygous. (C) All heterozygous. (D) All black. (E) 1:1 black to white. 51. The phenotypic ratio is: (A) 1:1 homozygous to heterozygous. (B) 3:1 heterozygous to homozygous. (C) All heterozygous. (D) All black. (E) 1:1 black to white. 52. In lab, you cross a blue-flowered plant variety with a yellow-flowered variety. You obtain 50% blue plants in the F 1 generation. The blue-flowered plants were probably : (A) homozygous dominant. (B) homozygous recessive. (C) heterozygous. (D) sterile. (E) it is impossible to confirm the parental genotype from the information given. 53. You could confirm the genotypes in the above question by: (A) performing a test-cross. (B) self-fertilizing the F 1 generation. (C) crossing with a homozygous recessive plant. (D) crossing with a homozygous dominant plant. (E) A and C. 54. Which of the following represents an individual that is homozygous for a recessive trait? (A) AA. (B) aa. (C) Aa. (D) AA and Aa. 7

8 SHORT ANSWER QUESTIONS: 55. A brown female mouse (Jane) is crossed with 2 black male mice (John and Bob). In the progeny of Jane and Bob 8 mice are black and 9 mice are brown, and in the progeny of Jane and John all 15 mice are black. What are the genotypes of the parents? 56. When Mendel used pollen from a dwarf strain of peas to fertilize the flowers of a true-breeding tall line, and planted the resulting seeds, only tall plants grew from them. When he crossed these hybrids to the dwarf plants he observed among the offspring 87 tall and 79 dwarf plants. Diagram the cross. 8

9 57. The diagram shows a cell that has 6 chromosomes and is in prophase of mitosis. Draw the cell in all the stages of meiosis. Make sure you label your diagrams. (In the exam you will be given a subset of the stages, so don t worry if this takes longer than the allotted time). Practice drawing these from memory you will have to do it in the exam. 9