Fall 2002 Be Sure to Put Your

Science 1101/12 Name

Fall 2002 Be sure to put your

Exam 1 name on the mark sense sheet as well

VERSION A

· If you fail to follow these instructions you may get a Zero on the exam.

· Be sure to put your name on the mark-sense sheet and on the exam booklet. Both the exam booklet and the mark-sense sheet must be turned in at the end of the period.

· Be sure to indicate the version (A, B, C, or D) on the mark sense sheet in the box marked “Key ID” in the upper left corner.

· You may write in the exam booklet, but only the mark-sense sheet will be graded. No other paper, scratch paper, etc. may be used.

· Students must turn in the exam before leaving the room for any reason. A student may not continue working on the exam after having left the room.

· Each question has a single correct answer. When a set of choices is used for more than one question, then a choice may be used more than once.

Multiple Choice. 50 questions, 2 pt each.

Questions 1 – 5 pertain to the digestion of triglycerides in the human digestive system.

1. Which of the following best describes the structure of a triglyceride molecule?

(a) A polymer composed of amino acids.

(b) A polymer composed of nucleotides.

(d) A glycerol molecule with fatty acids attached to it.

(e) Silicon bonded to four hydrogens.

2. Which of the following best describes the solubility of a triglyceride molecule in water?

(a) Hydrophobic (c) Amphipathic

(b) Hydrophilic (d) Ionic

3. The digestion of triglycerides requires the presence of lipase, an enzyme found in the small intestine. Which of the following best describes the structure of lipase?

(a) A polymer composed of amino acids.

(b) A polymer composed of nucleotides.

(d) A glycerol molecule with fatty acids attached to it.

(e) Silicon bonded to four hydrogens.

4. The action of lipase is to catalyze the addition of water molecules to the subunits from which triglyceride is composed, breaking the triglyceride into its subunits. Which of the following terms best describes this process?

(a) condensation reaction (c) oxidation reaction

(b) hydrolysis reaction (d) reduction reaction

5. Before lipase can act on triglyceride molecules, the triglyceride must be emulsified by a substance called bile. Bile is capable of forming micelles surrounding the triglyceride molecules, making it possible for water molecules and lipase to reach the triglyceride subunits. Which of the following terms best describes the solubility of bile in water?

(a) Hydrophobic (c) Amphipathic

(b) Hydrophilic (d) Ionic

6. Which of the following statements is true?

(a) Carbon and silicon are both capable of forming four covalent bonds per atom.

(b) Silicon is much less abundant on earth than carbon is.

(d) Silicon-silicon bonds are much more stable than silicon-oxygen bonds.

(e) More than one of the above.

7. A substance with a pH greater than seven

(a) is acidic, and has a greater [H+] than a neutral substance.

(b) is basic (alkaline), and has a greater [H+] than a neutral substance.

(d) is basic (alkaline), and has a lower [H+] than a neutral substance.

(e) None of the above are true.

8. A substance with a pH less than seven

(a) is acidic, and has a greater [H+] than a neutral substance.

(b) is basic (alkaline), and has a greater [H+] than a neutral substance.

(d) is basic (alkaline), and has a lower [H+] than a neutral substance.

(e) None of the above are true.

9. How is electricity produced by a coal-driven electrical generator?

(a) Burning coal is used to heat copper wires. The heat catalyzes a reduction reaction in that causes an electrical current (movement of electrons) in the wire.

(b) Burning coal is used to heat an unstable radioactive isotope (most often, U235). The tremendous heat that is produced causes a reduction reaction in the isotope, generating an electrical current (movement of electrons) in a coil of copper wire.

(c) Burning coal is used to boil water in a boiler to produce pressurized steam. The steam is used to hydrolyze the ends of a copper wire (made possible because of the low heat capacity of the copper). An electrical current is produced in the hydrolyzed copper.

(d) Burning coal is used to boil water in a boiler to produce pressurized steam. The steam is used to turn a steam-driven turbine (paddle-wheel) connected to a large coil of copper wire. The coil is rotated in a strong magnetic field. When a coil of copper wire is rotated in a magnetic field, it causes an electrical current (movement of electrons) in the wire.

The following information pertains to questions 10 – 11.

Consider the following chemical structures (labeled I, II, and III).

I. II. III.

10. List the structures in the order of most reduced carbon to least reduced carbon.

(a) I, II, III

(b) III, II, I

(d) II, I, III

(e) I, III, II

11. In which of the structures does the carbon have the greatest potential chemical energy (if reacted with oxygen)?

(a) I

(b) II

12. Which of the diagrams shows the structure of methane?

(a) I

(b) II

The following choices are used for questions 13 – 20.

(a) deductive reasoning (d) dependent variable

(b) inductive reasoning (e) independent variable

13. This is a possible explanation for an observed phenomenon

14. This is the unknown variable that a scientist measures in an experiment.

15. This is the best term for the thought process in which a scientist uses specific observations of a phenomenon to develop generalized explanations.

16. In an experiment, this is also known as the responding variable.

17. In the method known as data mining, scientist use computers to search through large numerical data bases to look for patterns in the data. For example, data mining techniques are used to look for patterns of human genes in the human genome project data base. Often, the scientists do not know what pattern they expect. Which term best describes the type of thought process used in data mining?

18. This is the best term for the thought process in which a scientist starts with a generalized explanation for a phenomenon and tests the explanation through controlled experimentation.

19. In an experiment, this is the variable that a scientist establishes or manipulates at the beginning of the experiment.

20. In a correctly drawn graph, this variable is plotted on the y-axis (vertical axis).

The following choices are used for questions 21 – 24.

(a) standard deviation

(b) average

(d) mode

21. This value is a measure of the dispersion in a data set.

22. This is the value that appears most frequently in a data set.

23. To calculate this number, you sum all of the values and divide by the number of values.

24. This is the value that occurs in the middle of a data set.

The following choices are used for questions 25 – 30.

(a) Electrons

(b) Neutrons

(d) More than one of the above

(e) None of the above

25. This structure is found in important biological monomers, such as glucose.

26. Consider these two isotopes of oxygen, oxygen-16 and oxygen-18. An atom of oxygen-16 differs from an atom of oxygen-18 in the numbers of these particles.

27. The atomic number of an atom is defined as the number of this type of particle.

28. The mass number of an atom is defined as the number of neutrons plus the number of this type of particle.

29. This type of particle has a positive electrical charge.

30. This type of particle has an atomic mass approximately equal to 1.

The following choices are used for questions 31 - 36.

(a) ionic bonds

(b) covalent bonds

31. This is the best term to describe the interactions between sodium and chloride ions in a salt crystal.

32. This term refers to the “sharing” of electrons between two atoms.

33. In an aqueous solution or suspension, this type of interaction is typically the strongest and most stable.

34. The bond between two monomer units in a dimer is this type of bond.

35. The bond formed in a condensation reaction is this type of bond.

36. The bond broken in a hydrolysis reaction is this type of bond.

37. Which of the following best describes the structure of a water molecule?

(a) A central oxygen bonded to two hydrogens, with all three atoms in a straight line.

(b) A central hydrogen bonded to another hydrogen and to an oxygen, with all three atoms in a straight line.

(d) A central hydrogen bonded to another hydrogen and to an oxygen, with an angle of about 110° between the second hydrogen and the oxygen.

The following choices are used for questions 38 – 42.

(a) potential energy

(b) kinetic energy

(d) atomic radiation

(e) chemical energy

38. This is the best term to describe energy that travels through space in the form of “packets” of energy waves called photons.

39. This is the best term to describe energy released when radioactive isotopes split apart or fuse together.

40. This is the best term to describe the energy associated with movement.

41. Radio waves, X-rays, and ultraviolet light are all examples of this type of energy.

42. This is the energy associated with the making or breaking of chemical bonds.

The following choices are used for questions 43 - 45.

(a) Hydrolysis Reaction

(b) Condensation Reaction

(d) Hydrophobic

(e) Heat Capacity

43. This is the best term to describe the breakdown of starch into glucose.

44. This is the best term to describe the manufacture of soap from fat.

45. This is the best term to describe why, when you go to the beach in early spring, the water may be still very cold even though the air temperature is much warmer.

The following choices are used for questions 46 - 50.

(a) carbohydrates

(b) proteins

(d) nucleic acids

46. Members of this group are composed mostly of carbon, hydrogen, and oxygen, and they have a large number of –OH groups attached to the carbons.

47. Many of the members of this group are enzymes.

48. The following diagram illustrates the monomer unit for this group:

49. DNA and RNA are examples of this group.

50. Genes are composed of a substance found in this group.

DID YOU PUT THE VERSION LETTER
IN THE KEY ID BOX ON YOUR MARK SENSE SHEET?

If not, you may make a zero on this test.

Science 1101/12 Version A Page 1