Cell Biology

Card Set Information

Cell Biology
2010-08-29 19:26:39

Chapter 1 Checkpoint Q's 1,2,9,12,14 & Q's at end of chapter 1 2,4,17,18 PLUS Chapter 2 All checkpoint & end of chapter questions
Show Answers:

  1. 1.1 Identify the oldest medical science.
    Anatomy is the oldest medical science.
  2. 1.2 Why is studying human anatomy and physiology important?
  3. Studying human anatomy and physiology is important because understanding normal physiology assists in recognizing when something abnormal occurs within the body.
  4. 1.9 What is the difference between gross anatomy and microscopic anatomy?
  5. Gross anatomy (often referred to as macroscopic anatomy) involves studying body structures that can be seen with the unaided eye. Microscopic anatomy is the study of body structures using a microscope to magnify the objects.
  6. 1.12 Identify major levels of organization from the simplest to most complex.
  7. The major levels organization from simplest to the most complex are the following: chemical (molecular) level -> cellular level -> tissue level -> organ level -> organ system level -> organism level
  8. 1.14 At which level of biological organization does a histologist investigate structures?
  9. A histologist investigates structures and properties at the tissue level of organization.
  10. 1.2.2What is Cytology?
  11. Study of cells
  12. 1.2.4 What is Histology?
  13. Study of tissue
  14. 1.2.17 The following is a list of the six levels of organization that make up the human body 1. Tissue, 2. Cell, 3. organ, 4. molecular, 5. organism, & 6. organ system. The correct order, from the smallest to largest , is
    4, 2, 1, 3, 6, 5.
  15. 1.2.18 The study of the structure of tissue is called
    A. Gross anatomy
    B. Cytology
    C. Histology
    D. Organology
  16. C. Histology
  17. 2.1 Define Atom.
  18. A. An atom is the smallest stable unit of matter.
  19. 2.2 Atoms of the same element that have different numbers of neutrons are called.
  20. A. Atoms of the same element that have the same atomic number but different numbers of neutrons are called isotopes.
  21. 2.3 How is it possible for two samples of hydrogen to contain the same number of atoms, yet have different weights?
  22. A. Hydrogen has three isotopes; hydrogen-1, with a mass of 1; deuterium, with a mass of 2; and tritium, with a mass of 3. The heavier sample must contain a high proportion of one or both of the heavier isotopes.
  23. 2.4 Define chemical bond and identify several types of chemical bonds.
  24. A. A chemical bond is an attractive force acting between two atoms that may be strong enough to hold them together in a molecule or compound. The strongest attractive forces result from the gain, loss, or sharing of electrons. Examples of such chemical bonds are ionic bonds and covalent bonds. In contrast, hydrogen bonds occur between molecules or compounds.
  25. 2.5 Which kind of bond holds atoms in a water molecule together? What attracts water molecules to one another?
  26. A. The atoms in a water molecule are held together by polar covalent bonds. Water molecules are attracted to one another by hydrogen bonds.
  27. 2.6 Both oxygen and neon are gases at room temperature. Oxygen combines readily with other elements, but neon does not. Why?
  28. A. Atoms combine with each other so as to gain a complete set of electrons in their outer energy level. Oxygen atoms do not have a full outer energy level, so they readily react with many other elements to attain this stable arrangement. Neon already has a full outer energy level and thus has little tendency to combine with other elements.
  29. 2.7 Identify and describe three types of chemical reactions important to human physiology.
  30. A. Three types of chemical reactions important to the study of human physiology include decomposition reactions, synthesis reactions, and exchange reactions. In a decomposition reaction, a chemical reaction breaks a molecule into smaller fragments. A synthesis reactions assembles smaller molecules into larger ones. In an exchange reaction, parts of the reacting molecules are shuffled around to produce new products.
  31. 2.8 In cells, glucose, a six-carbon molecule, is converted into three-carbon molecules by a reaction that releases energy. How would you classify this reaction?
  32. A. Because this reaction involves a large molecule being broken down into two smaller ones, it is a decomposition reaction. Because energy is released in the process, the reaction can also be classified as exergonic ( exothermic)
  33. 2.9 What is an enzyme?
  34. A. An enzyme is a protein that lowers the activation energy of a chemical reaction, which is the amount of energy required to start the reaction.
  35. 2.10 Why are enzymes needed in our cells?
  36. A. Without enzymes, chemical reactions could proceed in the body only under conditions that cells cannot tolerate (e.g., high temperatures). By lowering the activation energy, enzymes make it possible for chemical reactions to proceed under conditions compatible for life.
  37. 2.11 Distinguish between organic and inorganic compounds.
  38. A. Organic compounds contain carbon, hydrogen, and (in most cases) oxygen. Inorganic compounds generally do not contain carbon and hydrogen atoms as primary structural ingredients.
  39. 2.12 Explain how the chemical properties of water make life possible.
  40. A. Specific chemical properties of water that make life possible include its solubility (its strong polarity enables it to be used as an efficient solvent), its reactivity (it participates in many chemical reactions), its high heat capacity (it absorbs and releases heat slowly), and its ability to serve as a lubricant.
  41. 2.13 Define pH, and explain how the pH scale relates to acidity and alkalinity.
  42. A. pH is a measure of the concentration of hydrogen ions in fluids. Acid and base concentrations are measured in pH, which is the negative logarithm of hydrogen ion concentration, expressed in moles per liter. On the pH scale, 7 represents neutrality; vales below 7 indicate acidic solutions, and values above 7 indicate alkaline (basic) solutions.
  43. 2.14 What is the significance of pH in physiological systems?
  44. A. If the body is to maintain homeostasis and thus health, the pH of different body fluids must remain within a fairly narrow range.
  45. 2.15 Define the following terms: acid, base, and salt.
  46. A. An acid is a compound whose dissociation in solution releases a hydrogen ion and an anion; a base is a compound whose dissociation releases a hydroxide ion (OH-) or removes a hydrogen ion (H+)from the solution; a salt is an inorganic compound consisting of a cation other than H+ and an anion other than OH-.
  47. 2.16 How does an antacid help decrease stomach discomfort?
  48. A. Stomach discomfort is commonly the result of excessive stomach acidity ("acid indigestion"). Antacids contain a weak base that neutralizes the excess acid.
  49. 2.17 A food contains organic molecules with the elements C, H, and O in a ratio of 1:21:1. What class of compounds do these molecules belong to, and what are their major functions in the body?
  50. A. A compound with a H:H:O ration of 1:21:1 is a carbohydrate. The body uses carbohydrates cheifly as an energy source.
  51. 2.18 Describe lipids.
  52. A. Lipids are a diverse group of compounds that include fatty acids, eicosanoids, glycerides, steroids, phospholipids, and glycolipids. They are organic compounds that contain carbon, hydrogen, and oxygen in a ratio that does not approximate 1:21:1.
  53. 2.19 Which lipids would you find in human plasma membranes?
  54. A. Human plasma membranes primarily contain phospholipids, plus small amounts of cholesterol and glycolipids.
  55. 2.20 Describe a protein.
  56. A. Proteins are organic compounds formed from amino acids, which contain a central carbon atom, a hydrogen atom, an amino group (--NH2), a carboxylic acid group (--COOH), and a variable group, known as an R group or side chain. Proteins function in support, movement, transport, buffering, metabolic regulation, coordination and control, and defense.
  57. 2.21 How does boiling a protein affect its structural and functional properties?
  58. A. The heat of boiling breaks bonds that maintain the protein's tertiary structure, quaternary structure, or both. The resulting structural change, known as denaturation, affects the ability of the protein molecule to perform its normal biological functions.
  59. 2.22 Describe a nucleic acid.
  60. A. A nucleic acid is a large organic molecule composed of carbon, hydrogen, oxygen, nitrogen, and phosphorous. Nucleic acids regulate protein synthesis and make up the genetic material in cells.
  61. 2.23 A large organic molecule composed of the sugar ribose, nitrogenous bases, and phosphate groups is which kind of nucleic acid?
  62. A. Both DNA (Deoxyribonucleic acid) and RNA (Ribonucleic acid) contain nitrogenous bases and phosphate groups, but because this nucleic acid contains the sugar ribose, it is RNA.
  63. 2.24 Describe ATP
  64. A. Adenosine triphosphate (ATP) is a high-energy compound consisting of adenosine to which three phosphate groups are attached; the third is attached by a high-energy bond.
  65. 2.25 What molecule is produced by the phosphorylation of ADP?
  66. A. Phosphorylation of an ADP molecule yields a molecule of ATP.
  67. 2.26 Identify biochemical building block discussed in chapter 2 that are the components of cells.
  68. A. The biochemical building blocks that are components of cells include lipids (forming the plasma membrane), proteins (acting as enzymes), nucleic acids (directing the synthesis of cellular proteins), and carbohydrates (providing energy for cellular activities).
  69. 2.27 Define metabolic turnover.
  70. A. Metabolic turnover is the continuous breakdown and replacement of organic materials within cells.
  71. R2.2 What is the following type of decomposition reaction called?
    A - B - C - D + H2O ->A - B - C - H + HO - D
  72. ANSWER: Hydrolysis
  73. R2.3 The lightest of an atom's main constituents
    (a) carries a negative charge.
    (b) carries a positive charge.
    (c) plays no part in the atom's chemical reactions.
    (d) is found only in the nucleus.
  74. ANSWER: A
  75. R2.4 Isotopes of an element differ from each other in the number of
    (a) protons in the nucleus
    (b) neutrons in the nucleus
    (c) electrons in the outer shells
    (d) a, b, and c are all correct
  76. ANSWER: B
  77. R2.5 The number and arrangement of electrons in an atom's outer energy level determines the atom's
    (a) atomic weight
    (b) atomic number
    (c) molecular weight
    (d) chemical properties
  78. ANSWER: D
  79. R2.6 All organic compounds in the human body contain all of the following elements except
    (a) Hydrogen
    (b) Oxygen
    (c) Carbon
    (d) Calcium
    (e) Both A & D
  80. ANSWER: D
  81. R2.7 A substance containing atoms of different elements that are bonded together is called a(n)
    (a) molecule
    (b) compound
    (c) mixture
    (d) isotope
    (e) solution
  82. ANSWER: B
  83. R2.8 All the chemical reactions that occur in the human body are collectively referred to as
    (a) anabolism
    (b) catabolism
    (c) metabolism
    (d) homeostasis
  84. ANSWER: C
  85. R2.9 Which of the following equations illustrates a typical decomposition reaction?
    (a) A + B -> AB
    (b) AB + CD -> AD +CD
    (c) 2A2 +B2 -> 2A2B
    (d) AB -> A + B
  86. ANSWER: D
  87. R2.10 The speed, or rate, of a chemical reaction is influenced by
    (a) the presence of catalyst
    (b)the temperature
    (c) the concentration of the reactants
    (d) A, B, and C are all correct
  88. ANSWER: D
  89. R2.11 A ph of 7.8 in the human body typifies a condition referred to as
    (a) Acidosis
    (b) Alkalosis
    (c) Dehydration
    (d) Homeostasis
  90. ANSWER: B
  91. R2.12 A(n) ____________ is a solute that dissociates to release hydrogen ions, and a(n) ______________ is a solute that removes hydrogen ions from solution.
    (a) base, acid
    (b) salt, base
    (c) acid, salt
    (d) acid, base
  92. ANSWER: D