Card Set Information

2011-12-07 01:15:40
bio lab

lab study
Show Answers:

  1. Dependent Variable
    variable thats counted or measured or observed
  2. Independent Variable
    variable thats being manipulated
  3. Controlled Variable
    other independent variables, that stay consistent
  4. Level of Treatment
    value set for the indepependent variable
  5. Replication
    same procedure repeated
  6. Control
    benchmark, independent is held or omitted
  7. How do you construct a table?
    • All values of the same kind should be read down a column
    • Omit information and results
    • Headings should include units of measurement
    • Tables numbered consecutively throughout labs
    • Title located at top of table
    • Capatalize first and important words (not a, an, the)
    • When refering to table (Table 1.4) not "see the results in Table 1.4)
  8. How do you construct a figure?
    • Use graph paper and ruler to plot accurately
    • Independent variable on x-axis (horizontal)
    • Dependent variable on y-axis (vertical)
    • Use appropriate numerical range
    • Start with zero, to save space may use double tick marks between 0 and lowest #
    • Label axes to indicate variable, and units of measurement
    • Include legend with colors if needed
    • Choice bar/line graph depending onnature of variable beign graphed
    • Title below graph and numbered consecutively
    • Only first word capital and end with period
  9. Line Graph
    • show changes in the quanity of chosen variable
    • emphasize rise and fall
    • use to present continuous quanitive data
    • changes in dep. variable, weight, or measured over time
  10. Bar Graph
    • vertical bars are drawn down to horizontal axis
    • used for data to represent seperate or discontinuous groups or nonnumerical categories
    • emphsize discrete differences between the groups
    • when values on x axis are numerical but grouped together called histograms
  11. Compound Microscope
    • minimum of two magnifying lenses
    • binocular or monocular microscopes
  12. Head
    supports the two sets of magnifying lenses
  13. Ocular
    • the lens in the eyepiece
    • typically has a magnification of 10x
  14. Interpillary Distance
    • distance between the eyepieces
    • can be adjusted to suit your eyes
  15. Feild of View
    • is the circle of light that one sees in the microscope
    • has a pointer to point to an object
  16. Objectives
    • the three lenses on the revolving masterpiece
    • shortest to longesxt lense; 4x, 10x, 40x
    • clean lenses each time to avoid blurring or fogging of image
    • always use lense paper
  17. Scanning Lens
  18. Intermediate Lens
  19. High-Power Lens
  20. Arm
    supports the stage and condenser lens
  21. Condenser Lens
    • used to focus the light from the lamp through the specimen to be viewed
    • hieght can be adjusted by an adjustment knob
  22. Iris Diaphragm
    controls the the width of the circle of light and, therefore, the amount of light passing through the specimen
  23. Revolving Turret
    • if microscope has phase-contrast optics the condenser is housed here
    • when set on 0 the normal optical arrangement is in place (called brightfeild microscopy)
    • to use phase-contrast, turret settins must correspond to the magnifying power of the objective being used
  24. Stage
    • supports the specimen to be viewed
    • a mechanical stage can be moved right and left and back and fourth
  25. Stage Adjustment Knobs
    two adjustment knobs for the stage
  26. Stationary Stage
    the slide is secured under stage clips and moved slightly by hand while vieing the slide
  27. Coarse
    • adjustment for the distance between the stage and the objective
    • can also use the fine focus adjustment knobs
  28. Base
    Acts as a stand for the microscope and houses the lamp
  29. Light Intensity Lever
    adjusts the intesity of the light that passes through the specimen
  30. Stereoscopic (Dissecting) Microscope
    • low magnification of 7x to 30x
    • for viewing and manipulation relatively large objects
    • binocular feature creates the stereoscopic effect
    • depth of feild is much greater than with the CM so objects are in 3 dimension
    • the light source can be directed down onto as well as up through an object which permits viewing of objects too thick to transmit light
  31. Reflected or Inciden Light
    light directed down on the object
  32. Transmitted Light
    light passing through
  33. Working Distance
    distance between the specimen and the objective lens
  34. How do you compute the total magnification of the spectrum being viewed?
    multiply the magnification of the ocular lens by that of the objective lens
  35. If you move the slide to the left which direction does the image in the ocular move?
    to the right
  36. How do you prepare a wetmount?
    • place a drop of water and your specimen on the slide
    • using a disecting needle, slowly lower a coverslip onto the slide
    • be careful not to trsap air bubbles in the droplet
  37. At what angle do you lower the coverslip onto the slide?
    Place the coverslip at a 45 degree angle
  38. How do you properly handle the microscope?
    • with two hands
    • one holding the arm
    • the other supporting the base
  39. How do you properly put away the microscope?
    • rotate 4x objective into position
    • remove slide from stage
    • return phase-contrast condenser to 0 setting
    • lower stage completely
    • set light to lowest intesity
    • turn off
    • wrap the cord
    • cover with dust jacket
  40. Lysis
    cells swell and membranes burst
  41. Crenate
    cells shrivel and appear bumpy
  42. Osmosis
    type of diffusion of water through selectively permeable membrane from region where it is highly concentrated to a region where its concentration is lower
  43. Brownian Movement
    large particles suspended in water in motion
  44. What is the relationship between starch and iodine potassium iodide (I2KI)?
    I2KI tests for presence of starch when it is added to an unknown solution
  45. What was the permeability of the dialysis tubing?
    It was permeable to the glucose but not the starch into the beaker, and the I2KI got into the tubing because of the size of the molecules
  46. I2KI Test
    tests for presence of starch by turning purple or black when added to the unknown solution
  47. Benedict's Test
    • when reagent is added to unknown solution, solution is heated, if turns green, orange, or orange-red, a reducing sugar is present
    • if no reducing sugar is present the solution remains the color of the Benedict's reagent (blue)
  48. Hypertonic Solution
    has a greater concentration of solutes that cannot cross the membrane (nonpenetration solutes) than the solution on the other side of the membrane greater osmolarity (solute concentration expressed as molarity)
  49. Hypotonic Solution
    has a lower conentration of nonpenetrating solutes, or a lower osmolarity, than the solution on the otherside of the membrane
  50. Isotonic Solution
    when the two solutions are in equilibrium, the concentration of nonpenetrating solutes being equal on both sides of the membrane, the osmolarities are equal
  51. Net Flow
    the net flow of water is from the hypotonic solution to the hypertonic solution, when the solutions are isotonic, there is not net flow of water across the membrane
  52. What happens to water when it moves into red blood cells (animal cells) placed in a hypotonic solution?
    the cells swell and the membranes burst, or undergo lysis
  53. What happens when the water moves out of red blood cells (animal cells) placed in a hypertonic solution?
    the cells shrivel and appear bumpy or crenate
  54. Hypotonic solution in plant cells
    • as water moves into the cell and the cell's central vacuole, the cell's protoplast expands
    • the cell wall restricts the expansion, resulting in turgor pressure
    • a high turgor pressure will prevent further movement of water into the cell
  55. Hypertonic solution in plant cells
    • water moves out of the cell
    • the protoplast shrinks and pulls away from the cell wall call plasmolysis
    • the cell is then described as plasmolyzed
  56. Enzyme
    • proteins
    • biological catalysts, compounds that speed up a chemical reaction without being used up or altered in the reaction
    • a small amount of enzyme can alter a relatively enormous amount of substrate
  57. Substrate
    • the material with which the catalyst reacts
    • modified during the reaction to form a new product
  58. Active Site
    • active site of an enzyme that will bind with the substrate forming the enzyme-substrate complex
    • site where catalysis takes place and when complete dissociates into enzyme and product or products
  59. In the potato experiment what was the role of the catechol?
    catechol is a phenolic compound found in plant cells and is converted to benzoquinone, a pigment product by catechol oxidase
  60. What did the potato extract represent, or what did it contain that was important to this expirement?
    the extract is to test for the presence of catechol oxidase
  61. PTU
    • phenylthiourea is the specific inhibitor
    • known to combine with the copper in catechol oxidase and inhibits its enzymatic activity
  62. What was the enzyme in the potato extract experiment?
    catechol oxidase and amylase
  63. What was the substrate in the potato extract expirement?
  64. Why was the concentration of catechol increased in excersize 4.2?
    adding additional substrate (catechol) will not reverse the inhibition if it is a noncompetitive inhibition
  65. Name three variables that may affect the activity of amylase.
    enzyme concentration, pH, and temperature
  66. Effect of temperature on Amylase
    (expirement we used)
    • chemical reactions accelerate as temperature rises, however high temperatures denature the protein
    • After conducting an expirement at four different temperatures, in four different test tubes, the results yeilded that between 22 and 37 degrees the reaction time is the quickest, where as it slows down at higher temperatures of 80 degrees
  67. Noncompetitive Inhibition
    • the inhibitor binds to a part of the enzyme that is not the active site, in so doing it changes the nature of the enzyme so that its catalytic properties are lost
    • 1) either the NI itself physically blocks the acces to the active site
    • 2) it causes a conformational change in the protein, thus inactivating the active site
    • the inhibitor can become unbound, reversing the inhibition
    • unlike competitive inhibition, adding additional substrate will not reverse the inhibition
  68. Competitive Inhibition
    • when a molecule structurally similiar to the substrate for a particular reaction competes for a position at the active site on the enzyme
    • tieing up the enzyme so that it is not available to the substrate
    • competitive inhibition can be reversed if the concentration of substrate is raised to sufficiently high levels while the concentration of the inhibitor is held constant
  69. Heterotrophic
    capable of utilizing only organic materials as a source of food
  70. Plasmodesmata
    strands of cytoplasm that extend through plant cells to connect to other cells
  71. Cytoplasmic Streaming
    • circulation of cytoplasm caused by shortening and lengthening of "microfilaments" of actin
    • motion of the chloroplasts (and other organelles) around the periphery of the cell
  72. Yeast Cell
    circular, cannot distinguish any structures

    (a ton of tiny circles with cell walls-the dark outside)
  73. Onion Cell
    red pigmentation, does not move out of cell with water

    (looks like red bricks, the outline of each is cell wall, the nucleus is the dark circles, and the cytoplasm is the area inbetween)
  74. Elodea Cell
    be able to label the cell wall, cytoplasm, chloroplasts, and plasma membrane
  75. Aerobic
    • utilizing oxygen
    • includes cellular respiration, krebs, and electron transport chain
  76. Anaerobic
    • without oxygen
    • include fermentation and glycolysis
  77. Reactant
  78. Product
  79. What is the difference between cellular respiration and fermentation?
    cellular respiration is aerobic and gives greater yield of ATP, and fermentation is anaerobic
  80. Independent Investigation of fermentation
    beer and wine yeast
    We predicted that beer yeast will ferment faster than wine yeast, and we experimented having 4 different tests tubes with different amouts of yeast and glucose solution. There was a control tube for each yeast, and the results supported the hypothesis
  81. Absorption Spectrum
    • absorption pattern for a particular pigment, showing the relative absorbance at different wavelengths of light
    • can be determined with a spectrophotmeter or colorimeter
  82. Action Spectrum
    • a graph that illustrates the efficacy of different wavelengths of light in promoting photosynthesis
    • the efficacy of various wavelengths of light is measured by the production of oxygen and the clustering of bacteria
  83. Which colored filters allow for the greatest photosynthesis activity?
    blue because black absorbs all wavelengths even white
  84. What was the purpose of dropping I2KI on the boiled geranium and Coleus leaves?
    • Because it stains starch purple-black
    • a change fromthe yellow-amber color of the iodine solution to a purple-black solution is a positive test for starch production which determines photosynthesis
  85. How do different polarities affect the rate of movement of compunds on chromatography paper?
    The most polar will travel the slowest up the chromatography paper compared to the least polar will travel the highest on the chromatography paper over the same amounts of time
  86. Analyzing an abosorbtion spectrum
    • Use a spectrophotometer or colorimeter
    • List the pigments extracted and the optimum wavelengths of light for each
    • Decide which pigment is most important in photosynthesis (the one that has a higher abosorbion at more wavelengths)