Test 2

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Test 2
2010-10-18 17:28:29

Chapter 6
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  1. The branch of chemistry concerned with energy changes
  2. The capacity to do work
  3. Energy of motion
    Kinetic energy
  4. Stored energy
    Potential energy
  5. An atom or molecule that loses an electron
  6. An atom or molecule that gains an electron is said to be reduced
  7. Play a key role in the flow of energy through biological systems; always take place together, because every electron that is lost by one atom is gained by another atom
    Oxidation-reduction or redox reactions
  8. Concerns the amount of energy in the universe
    First Law of Thermodynamics
  9. A measure of the random motion of molecules (and therefore a measure of one form of kinetic energy)
  10. Concerns the transformation of potential energy into hear, or random molecular motion
    Second Law of Thermodynamics
  11. The disorder in the universe
  12. Amount of energy actually available to break and subsequently form other chemical bonds; the energy available to do work in any system
    Free energy
  13. Energy contained in a molecule's chemical bonds
  14. Any reaction that requires an input of energy
  15. Reactions release the excess free energy as heat; "outward energy"
  16. Numeric value of the equilibrium
    Equilibrium constant
  17. The extra energy needed to destabilize existing chemical bonds and initiate a chemical reaction
    Activation energy
  18. The process of influencing chemical bonds in a way that lowers the activation energy needed to initiate a reaction
  19. The chief "currency" all cells use for their energy transactions is the nucleotide ___________________________.
    Adenosine triphosphate (ATP)
  20. In most reactions involving ATP, only the outermost high-energy phosphate bond is hydrolyzed, cleaving off the phosphate group on the end
    Adenosine diphosphate (ADP)
  21. Can be created by hydrolysis of pyrophosphate
    Inorganic phosphate (Pi)
  22. Both of the two terminal phosphates can be hydrolyzed to release energy
    Adenosine monophosphate (AMP)
  23. The molecules that will undergo the reaction
  24. Vertebrate red blood cells overcome this problem by employing an enzyme within their cytoplasm
    Carbonic ambydrase
  25. Most enzymes are globular proteins with one or more pockets or clefs
    Active sites
  26. Substrates bind to the enzyme at these active sites
    Enzyme-substrate complex
  27. A way that enzymes form associations by carrying out reaction sequences; Often several enzymes catalyzing different steps of a sequence of reactions are associated with one another in noncovalently bonded assemblies
    Multienzyme complexes
  28. Some ribozymes have folded structures and catalyze reactions on themselves
    Intramolecular catalysis
  29. Ribozymes act on other molecules without being changed themselves
    Intermolecular catalysis
  30. The rate of an enzyme-catalyzed reaction also increases with temperature, but only up to a point
    Optimum temperature
  31. A substance that binds to an enzyme and decreases its activity
  32. The end product of a biochemical pathway acts as an inhibitor of an early reaction in the pathway
    Feedback inhibition
  33. Compete with the substrate for the same active state occupying the active site and thus preventing substrates from binding
    Competitive inhibitors
  34. Many enzymes can exist in either an active or inactive conformation
    Allosteric enzymes
  35. Bind to the enzyme in a location other than the active site, changing the shape of the enzyme and making it unable to bind to the substrate
    Noncompetitive inhibitors
  36. Most noncompetitive inhibitors bind to a specific portion of the enzyme
    Allosteric site
  37. A substance that binds to an allosteric site and reduces enzyme activity
    Allosteric inhibitor
  38. Binds to allosteric sites to keep an enzyme in it's active configuration, thereby increasing enzyme activity
    Allosteric activator
  39. Enzyme function is often assisted by additional chemical components
  40. When the cofactor is a nonprotein organic molecule
  41. Living chemistry, the total of all chemical reactions carried out by an organism
  42. Chemical reactions that expend energy to build up molecules
    Anabolic reactions or anabolism
  43. Reactions that harvest energy by breaking down molecules
    Catabolic reactions or catabolism
  44. Reactions in a cell occur in sequences
    Biochemical pathways
  45. A form of photosynthesis that does not produce oxygen; Found in four different bacterial groups: purple bacteria, green sulfur bacteria, green nonsulfer bacteria, and heliobacteria
  46. A form of photosynthesis that does produce oxygen; Found in cyanobacteria, seven groups of algae, and essentially all land plants
  47. The first two stages of photosynthesis require light and are commonly called:
    Light-dependent reactions
  48. The third state, the formation of organic molecules from CO2; takes place via a cyclic series of reactions
    Carbon fixation
  49. As long as ATP and NADPH are available, the carbon fixation reactions can occur either in the presence or in the absence of light. These reactions are called ________________________.
    Light-independent reactions
  50. The internal membrane of chloroplasts; A continuous phospholipid bilayer organized into flattened sacs that are found stacked on one another in columns
    Thylakoid membrane
  51. Flattened sacs that are found stacked on one another in columns
  52. Photosynthetic pigments for capturing light energy along with the machinery to make ATP
  53. Connections between grana are _______________.
    Stroma lamella
  54. A semiliquid substance that surrounds the thylakoid membrane system
  55. In the thylakoid membrane, photosynthetic pigments are clustered together to form ___________________, which show distinct organization within the thylakoid
  56. H+ ions and electrons generated by the splitting of water were used to convert CO2 into organic matter in a process called __________________.
    Carbon fixation
  57. Molecules that absorb light energy in the visible range
  58. A particle of light; acts like a discrete bundle of energy
  59. A beam of light is able to remove electrons from certain molecules, creating an electrical current; Occurs when photons transfer energy to electrons
    Photoelectric effect
  60. The range and efficiency of photons it is capable of absorbing
    Absorption spectrum
  61. The main photosynthetic pigment in plants and cyanobacteria and the only pigment that can act directly to convert light energy to chemical energy
    Chlorophyll a
  62. Complements and adds to the light absorption of chlorophyll a
    Chlorophyll b
  63. Secondary light-absorbing pigments
    Accessory pigment
  64. Pigments contain a complex ring structure with alternating single and double bonds
    Porphyrin ring
  65. The relative effectiveness of different wavelengths of light in promoting photosynthesis
    Action spectrum
  66. Consist of carbon rings linked to chains with alternating single and double bonds
  67. Accessory pigments found in cyanobacteria and some algae; composed of proteins attached to a tetrapyrrole group
  68. a light-harvesting complex; captures photons from sunlight and channels than to the reaction center chlorophylls
    Antenna complex
  69. A transmembrane protein-pigment complex
    Reaction center
  70. A photon of light is captured by a pigment; Excites an electron within the pigment
    Primary photoevent
  71. The excitation energy is transferred to the reaction center which transfers an energetic electron to an acceptor molecule, initiating electron transport
    Charge separation
  72. The excited electrons are shuttled along a series of electron carrier molecules embedded within the photosynthetic membrane
    Electron transport
  73. The protons that accumulate on one side of the membrane now flow back across the membrane through ATP synthase where chemiosmotic synthesis of ATP takes place, just as it does in aerobic respiration
  74. An absorption peak of 700 nm, so its reaction center pigment is called P700+
    Photosystem I
  75. Has an absorption peak of 680 nm, so its reaction center pigment is called P600+
    Photosystem II
  76. Two photosystems are connected by a complex of electron carriers
    Cytochrome/b6-f complex
  77. The path of electrons is not a circle--the electrons ejected from the photosystems do not return to them, but rather end up in NADPH
    Noncyclic photophosphorylation
  78. Can by explained a mechanism involving two photosystem absorbs preferentially in the red, the other in the far-red
    Enhancement effect
  79. Illustrates the two electron-energizing steps, one catalyzed by each photosystem
    Z diagram
  80. The primary electron acceptor for the light-energized electrons leaving photosystem II
    Quinone molecule
  81. The reduced quinone passes the excited electron pair to a proton pump called
    b6-f complex
  82. A small, copper-containing protein that carries the electron pair to photosystem I
  83. Electrons are passed to an iron-sulfur protein
  84. The cycle of reactions that allow carbon fixation
    Calvin cycle
  85. Because the first intermediate of the cycle, phosphoglycerate, contains three carbon atoms this process is called
    C3 Photosynthesis
  86. Energy-rich 5-carbon sugar
    Ribulose 1, 5-bisphosphate (RuBP)
  87. A large, 16-subunit enzyme found in the chloroplast stroma
    Ribulose bisphosphate carboxylase/ oxygenase
  88. O2 is incorporated into RuBP, which undergoes additional reactions that actually release CO2
  89. Plants that fix carbon using only C3 photosynthesis
    C3 plants
  90. The capture of CO2 occurs in one cell and the decarboxylation occurs in an adjacent cell
    C4 plants
  91. Perform both reactions in the same cell, but capture CO2 using PEP carboxylase at night, then decarboxylase during the day
    CAM (crassulacean acid metabolism) plants
  92. Plants, algae, and some bacteria harvest the energy of sunlight through photosynthesis, converting radient energy into chemical energy. These organisms, along with a few others that use chemical energy in a similar way, are called _____________.
  93. All other organisms live on the organic compounds autotrophs produce, using them as food.
  94. Where energy is harvested; the oxidation of organic compounds to extract energy from chemical bonds.
    Cellular respiration
  95. The electrons lost are accompanied by protons, so that what is really lost is a hydrogen atom, nut just an electron
  96. An enzyme catalyzes a redox reaction involving an energy-rich substrate molecule, with the help of a cofactor, ___________.
    Nicotinamide adenosine dinucleotide (NAD+)
  97. High-energy electrons from the initial chemical bonds have lost much of their energy, and these depleted electrons are transferred to a final electron acceptor. When this acceptor is oxygen, the process is called _________________.
    Aerobic respiration
  98. High-energy electrons from the initial chemical bonds have lost much of their energy, and these depleted electrons are transferred to a final electron acceptor. When the acceptor is an inorganic molecule other than oxygen, the process is called ________________.
    Anaerobic respiration
  99. High-energy electrons from the initial chemical bonds have lost much of their energy, and these depleted electrons are transferred to a final electron acceptor. When the acceptor is an organic molecule, the process is called _______________.
  100. Located in the mitochondrial inner membrane; electrons are passed to another set of electron carriers
    Electron transport chain
  101. The initial breakdown of glucose
  102. Protein kinases that are regulated by cyclin binding and its phosphorylation state
    Cyclin-dependent kinases
  103. The phase in which the cell synthesizes a replica of it's genome
  104. The normal number of chromosomes in a cell reflecting the equal contribution from both parents
    diploid (2n)
  105. The overall process of genome duplication, segregation, and division of cellular contents
    Cell cycle
  106. A dislike structure that functions as an attachment site for microtubules to separate chromatids
  107. The two replicas of a single chromosome held together at their centromeres by cohesion proteins
  108. The protein that forms microtubules, which cells extensively synthesize in G2
  109. The region on the chromosome where two sister chromatids are held together and the kinetochore forms
  110. The phase in the cell cycle during which mitochondria and other organelles replicate
  111. The phase in mitosis when chromosomes are clustered at opposite poles and the spindle apparatus disappears
  112. A resting state that cells often enter before resuming cell division
  113. The first stage of mitosis in which the chromosomes condense and the spindle apparatus is assembled
  114. A domain of chromatin in which the genes are being actively expressed
  115. The phase in the cell cycle when the cytoplasm divides creating two daughter cells
    Cytokinesis (C)
  116. The mitotic phase in which chromosomes are pulled to opposite poles and the spindle poles move apart
  117. A radial array of microtubules extended from the centrioles toward the nearby plasma membrane
  118. The complex of DNA wrapped around histone proteins that look like beads on a string
  119. A pair of microtubule-organizing centers replicated in G2 to produce one for each pole of the cell
  120. The particular array of chromosomes an individual organism possesses
  121. The mitotic phase in which all of the chromosomes are aligned at the equator of the cell
  122. The phase in the cell cycle in which the spindle apparatus assembles and sister chromatids move apart
    Mitosis (M)
  123. The process used by bacteria to duplicate genetic information and segregate it into two daughter cells
    Binary fission
  124. A domain of chromatin in which the genes are not actively expressed
  125. One complete set of chromosomes necessary to define an organism
    Haploid (n)
  126. The portion of the cell cycle between cell divisions consisting of G1, S, G2 together
  127. Mutations in these genes have dominate, gain-of-function effects leading to cancer
  128. The space between the daughter cells in plants that is filled with pectins
    Middle lamella
  129. When both copies of this type of gene lose function, there is a loss of control of cell proliferation
    Tumor suppressor
  130. Trigger intracellular signaling systems and can override cellular controls that inhibit cell division
    Growth factors
  131. Genes that can, when introduced into a cell, cause it to become a cancer cell
  132. An expanding membrane portion in plants that grows outward and fuses with the plasma membrane
    Cell plate
  133. Marks the securing protein for degradation by the proteosome
    Anaphase-promoting complex
  134. A division formed at the midpoint of a bacterial call facilitated by the FtsZ protein assembling there
  135. Regulatory proteins that are required to activate Cdks
  136. Composed of both cyclin and a kinase and acts as a positive regulator of cell cycle progression in frogs
    M-phase-promoting factor
  137. Each of the maternal and paternal copies of the came chromosome in a pair
  138. Proteins that have an overall positive charge that promote and guide the coiling of DNA
  139. The primary growth phase of the cell encompassing the major portion of the cell cycle
  140. The cells that will eventually undergo meiosis to produce gametes
    Germ-line cells
  141. Sites of contact between homologous chromosomes that are produced as a result of crossing over
  142. The number of chromosomes found in gametes (eggs or sperm)
  143. Gametes that contain an improper number of chromosomes and can lead to spontaneous abortion
    Aneuploid gametes
  144. The failure of chromosomes to move to opposite poles in either meiotic division
  145. The different possible combinations of maternal and paternal chromosomes in gametes
    Independent assortment
  146. An elaborate structure consisting of homologues closely paired with a lattice of proteins between them
    Synaptonemal complex
  147. Structures thought to contain the enzymatic machinery necessary to break and rejoin chromatids
    Recombination nodules
  148. The process by which two haploid gametes fuse to form a new diploid cell
  149. Phase of meiosis in which homologous chromosomes align and kinetochore microtubules attach to each
    Metaphase I
  150. Segregate to opposite poles during the meiosis II to produce four haploid cells
    Sister chromatids
  151. A specialized reduction division that produces cells with half the normal number of chromosomes
  152. Division, beginning without DNA replication, that resembles mitosis and produces four haploid cells
    Meiosis II
  153. A process unique to meiosis in which homologues exchange chromosomal material
    Crossing over
  154. The nonreproductive cells found in embryos and mature individuals
  155. Somatic cells
  156. The imaginary plane along which homologous chromosomes align in metaphase I
    Metaphase plate
  157. Cells (egg or sperm) resulting from a meiotic division of germ-line cells, specialized for sexual reproduction
  158. Phase of meiosis in which homologous cluster at the poles of the cells and the nuclear envelope reforms
    Telophase I
  159. The initial reduction division in which homologous chromosomes are segregated to two daughter cells
    Meiosis I
  160. A single cell with a diploid number of chromosomes resulting from the fusion of an egg and a sperm
  161. Reproductive life cycle that involves an alternation between haploid and diploid cells, or organisms
    Sexual reproduction
  162. The process whereby homologous chromosomes find each other and become closely associated
  163. Phase of meiosis in which the chromosomes begin to condense and the microtubule spindle begins to form
    Prophase I
  164. Two sets of chromosomes present in the somatic cells of adult individuals
  165. Meiosis in which there is no recombination, but the homologous chromosomes still divide accurately
    Achiasmate segregation
  166. One of the two copies of a chromosome, each derived from one parent, found in diploid cell
    Homologous chromosome
  167. Phase of meiosis when chiasmata and broken as spindle fibers shorten and homologous pairs are pulled apart
    Anaphase I