Microbiology chapter 2

8. What is the maximum number of electrons in the first energy shell of an atom? A. 2 B. 4 C. 8 D. 18 E. 32

2

7. What is the maximum number of electrons in the second energy shell of an atom? A. 2 B. 4 C. 8 D. 18 E. 32

8

3. The electrons of an atom are A. Always equal to the number of protons B. Used to determine the atomic weight C. Carrying a positive charge D. Used to determine the atomic number E. Always in full orbitals

A. Always equal to the number of protons

32. Organic chemicals always have a basic framework of the element _____ bonded to other atoms. A. Carbon B. Nitrogen C. Oxygen D. Hydrogen E. Phosphorous

A. Carbon

5. The subatomic particles that surround the nucleus are the A. Electrons B. Protons C. Neutrons D. Protons and neutrons E. Protons and electrons

A. Electrons

40. What part of a phospholipid forms hydrophobic tails? A. Fatty acids B. Glycerol C. Phosphate D. Alcohol E. All of the choices are correct

A. Fatty acids

6. Isotopes are atoms of the same element that differ in their A. Neutron number B. Electron number C. Proton number D. Atomic number E. Chemical properties

A. Neutron number

17. A reaction where an electron is lost is called A. Oxidation B. Reduction C. Ionization D. Decomposition E. Dissolution

A. Oxidation

31. Which of the following functional groups is mismatched to the organic compound? A. Phosphate-carbohydrates B. Sulfhydryl-proteins C. Amino-proteins D. Hydroxyl-alcohols E. Carboxyl-fatty acids

A. Phosphate-carbohydrates

20. Hydrogen bonds A. Result from attractive forces between molecules with polar covalent bonds B. Result from attractive forces between molecules with polar ionic bonds C. Result from attractive forces between molecules with non-polar covalent bonds D. Result from attractive forces between molecules with non-polar ionic bonds E. Are the strongest bonds between molecules

A. Result from attractive forces between molecules with polar covalent bonds

59. The purine___ always binds with the pyrimidine__ in DNA and RNA. A. guanine, cytosine B. cytosine, guanine C. adenine, guanine D. thymine, guanine

A. guanine, cystosine

54. Purines and pyrimidines are components in the building block units of all A. Nucleic acids B. Carbohydrates C. Polysaccharides D. Amino acids E. Enzymes

A. nucleic acids

12. What would be the valence number of electrons in the sulfur (S) atom? A. 2 B. 6 C. 8 D. 16 E. 32

B. 6

23. Which of the following represents a synthesis reaction? A. AB ® A + B B. A + B ® AB C. AB + XY ® AX + BY D. AB + XY « AX + BY E. None of the choices are correct

B. A + B ® AB

34. All of the following are monosaccharides except A. Glucose B. Glycogen C. Fructose D. Ribose E. Deoxyribose

B. Glycogen

14. Polar molecules A. Have an equal charge distribution B. Have an unequal charge distribution C. Are insoluble in water D. Always contain carbon E. Always involve oxygen

B. Have an unequal charge distribution

26. Ionic compounds are A. Hydrophobic B. Hydrophilic C. Are acidic in solution D. Are basic in solution E. Always form salts in solution

B. Hydrophilic

19. Ionic bonds A. Result from sharing electrons B. Result from transferring electrons C. Results from like charge attraction D. Are the weakest chemical bonds E. Always involve carbon

B. Result from transferring electrons

27. A solution is composed of one or more substances called _____ that are uniformly dispersed in a dissolving medium called a _____. A. Solvent, solute B. Solute, solvent C. Neither solvent, solute nor solute, solvent D. Both solvent, solute and solute, solvent

B. Solute, solvent

39. All of the following are lipids except A. Cholesterol B. Starch C. Phospholipid D. Wax E. Triglyceride

B. Starch

55. Which of the following is not a pyrimidine? A. Uracil B. Adenine C. Thymine D. Cytosine E. All of these are pyrimidines

B. adenine

47. Which amino acid contains sulfur atoms that form covalent disulfide bonds in its tertiary structure? A. Valine B. Cysteine C. Serine D. Alanine E. Tyrosine

B. cysteine

56. During protein synthesis, ____ RNA is made to be a copy of a gene from the DNA. A. Transfer B. Messenger C. Ribosomal D. All of the choices are correct

B. messenger

58. An example of an amphipathic molecule found in living cells is: A. glucose B. phospholipid C. protein D. nucleic acids

B. phospholipid

18. An atom has gained an electron. It has been A. Oxidized B. Reduced C. Ionized D. Deionized E. Neutralized

B. reduced

49. The a - helix is a type of _____ protein structure. A. Primary B. Secondary C. Tertiary D. Quaternary E. None of these

B. secondary

9. Protons and neutrons make up the atom's central core referred to as its A. Valence number B. Isotope C. Nucleus D. Center of gravity E. None of the choices are correct

C nucleus

60. You are asked to make a 1M solution of Sodium Bicarbonate or Baking Soda (NaHCO3 ) for a DNA extraction lab. How many gram(s) of sodium bicarbonate (NaHCO3 ) should be added to 1L of water to make the required solution? Use the table of atomic masses to help you. A. 29 g B. 62 g C. 84 g D. 91.1 g E. Element Atomic mass H 1.00 C 12.00 O 16.00 Na 23.00 K 39.1

C. 84g

38. Starch is the primary storage food for all of the following except A. Green plants B. Algae C. Animals D. Some fungi E. All of these store food as starch

C. Animals

33. Most biochemical macromolecules are polymers, which are A. Chains of hydrophobic molecules B. Chains of electrolytic molecules C. Chains of repeating monomers D. Chains of repeating carbohydrates E. Chains of hydrogen bonds

C. Chains of repeating monomers

4. All of the following pertain to the atom carbon-14 except A. Has 6 protons B. Has 6 electrons C. Has 14 neutrons D. Is an isotope of carbon E. All of the choices pertain to carbon-14

C. Has 14 neutrons

29. A solution of pH 7 compared to a solution of pH 9 A. Is more basic B. Has no OH- ions C. Has more H+ ions D. Has a higher pH E. All of the choices are correct

C. Has more H+ ions

21. Atoms that gain or lose electrons become charged particles called A. Cations B. Anions C. Ions D. Isotopes E. All of the choices are correct

C. Ions

1. Anything that occupies space and has mass is called A. Atomic B. Living C. Matter D. Energy E. Space

C. Matter

53. A student forgot to label a beaker containing a DNA solution and a beaker containing a glucose solution. If chemical analysis was performed to identify the contents of each beaker, which of the following would be found in the beaker of DNA but not in the beaker with glucose? A. Amino acids B. Hydrogen and oxygen atoms C. Nitrogen and phosphorus D. Fatty acids E. Carbon atoms

C. Nitrogen and phosphorus

51. Which pertains to DNA but not to RNA? A. Contains ribose B. Contains adenine C. Contains thymine D. Contains uracil E. Contains nucleotides

C. contains thymine

48. What type of bonds are formed by dehydration synthesis between adjacent amino acids? A. Glycosilic B. Ester C. Peptide D. Disulfide E. Phosphate

C. peptide

43. The lipid group that is the major component of cell membranes are the A. Prostaglandins B. Waxes C. Phospholipids D. Steroids E. Triglycerides

C. phospholipids

30. A solution of pH 7 compared to a solution of pH 9 A. 2 times more acidic B. 20 times more acidic C. 20 times more basic D. 100 times more acidic E. 100 times more basic

D. 100 times more acidic

24. Which of the following represents a reversible reaction? A. AB ® A + B B. A + B ® AB C. AB + XY ® AX + BY D. AB + XY « AX + BY E. None of the choices are correct

D. AB + XY « AX + BY

50. One nucleotide contains A. One phosphate B. One pentose sugar C. One nitrogen base D. All of the choices are correct E. None of the choices are correct

D. All of the choices are correct

13. Polar molecules are composed of covalently bonded A. Identical atoms B. Carbon atoms C. Ions D. Atoms of different electro negativity E. Atoms of identical electro negativity

D. Atoms of different electro negativity

16. Cations are a(n) A. Charged subatomic particles B. Atoms that have gained electrons C. Atoms that have gained neutrons D. Capable of forming ionic bonds with anions E. Atoms without protons

D. Capable of forming ionic bonds with anions

22. Substances that release ions when dissolved in water and conduct electricity are A. Covalent B. Nonpolar C. Electrons D. Electrolytes E. Solvents

D. Electrolytes

28. Which term does not belong in this list? A. Lactic acid B. Vinegar C. Hydrogen ion donor D. PH 8 E. Acidic

D. PH 8

35. Which of the following would have glycosidic bonds? A. Triglycerides B. Monosaccharides C. Polypeptides D. Polysaccharides E. ATP

D. Polysaccharides

15. Covalent bonds A. Result from losing electrons B. Are always polar C. Are always non-polar D. Result from sharing electrons E. Result from gaining electrons

D. Result from sharing electrons

41. A fat is called _____ if all carbons of the fatty acid chain are single bonded to 2 other carbons and 2 hydrogens. A. Unsaturated B. Polyunsaturated C. Monounsaturated D. Saturated E. None of the choices are correct

D. Saturated

52. ATP is best described as A. An enzyme B. A double helix C. An electron carrier D. The energy molecule of cells E. All of the choices are correct

D. The energy molecule of cells

57. Characteristics of shared by all cells include: A. a membrane serving as a cell boundary B. the possession of genetic information C. the presence of cellular fluid D. All of these

D. all of these

45. An amino acid contains all of the following except A. An amino group B. A carboxyl group C. A variable R group D. An a carbon E. A nitrogen base

E. A nitrogen base

37. C6H12O6 + C6H12O6 ® C12 H22O11 + H2O represents A. Formation of a peptide bond B. A decomposition reaction C. Denaturation D. Formation of a polysaccharide E. Dehydration synthesis

E. Dehydration synthesis

46. Which is not true about enzymes? A. Found in all cells B. Are catalysts C. Participate in the cell's chemical reactions D. Can be denaturated by heat and other agents E. Have high-energy bonds between phosphates

E. Have high-energy bonds between phosphates

2. The electrons of an atom are A. Always equal to the number of neutrons in an atom B. Found in the nucleus C. Used to determine atomic number D. Positively charged E. Moving in pathways called orbitals

E. Moving in pathways called orbitals

36. All of the following are polysaccharides except A. Dextran in some bacterial slime layers B. Agar used to make solid culture media C. A cell's glycocalyx D. Cellulose in certain cell walls E. Prostaglandins in inflammation

E. Prostaglandins in inflammation

25. The important solvent associated with living things is A. Carbon dioxide B. Sodium chloride C. Ethyl alcohol D. Benzene E. Water

E. Water

44. The building blocks of an enzyme are A. Nucleotides B. Glycerol and fatty acids C. Monosaccharides D. Phosphate, glycerol, fatty acids E. Amino acids

E. amino acids

11. Two or more atoms bonded together are called a/an A. Ion B. Isotope C. Element D. Electrolyte E. Molecule

E. molecule

10. The valence number is the A. Number of protons B. Number of neutrons C. Atomic weight D. Number of inner most electrons E. Number of outer most electrons

E. number of outer most electrons

42. The lipid group that serves as energy storage molecules are A. Prostaglandins B. Waxes C. Phospholipids D. Steroids E. Triglycerides

E. triglycerides

62. Electrons that participate in chemical bonding are typically located closest to the nucleus. True False

False

63. Water molecules are non-polar molecules. True False

False

65. A covalent bond is formed between an anion and a cation. True False

False

67. The concentration of a solution expresses the amount of solvent present. True False

False

70. All proteins are enzymes. True False

False

72. Nucleic acids have primary, secondary, tertiary and quaternary levels of organization. True False

False

61. Elements have predictable chemical properties. True False

True

64. Polar molecules have more reactivity compared to non-polar molecules. True False

True

66. Only charged atoms can form ionic bonds. True False

True

68. If solution A has a lower pH compared to solution B, then solution A is more acidic than solution B. True False

True

69. The only part of an amino acid that differs from other amino acids is its R group. True False

True

71. The most important outcome of polypeptide intra-chain bonding and folding is the unique shape of the protein. True False

True