Instrumentation Final

  1. What is a thermocycler?
    A PCR machine that amplified DNA fragments millions of times
  2. How does the PCR reaction work?
    • 94 Heat- denature
    • 52 Cool- anneal primers to template
    • 72 Warm- extends and replicates
    • Repeats 35 cycles
  3. What is a spectrophotometer?
    A device for measuring light intensity
  4. What 4 things can happen when light strikes matter?
    • Transmitted
    • Reflected
    • Scattered
    • Absorbed
  5. What is transmittance?
    The ratio of amount of light passed through the sample, compared to the amount of light passed through the blank
  6. What is the equation for absorbance?
    Absorbance = -log (transmittance)
  7. What is the relationship between concentration compared to transmission and absorbance? (as concentration increases)
    • Transmission decreases
    • Absorbance increases
  8. What is the equation for the line for concentration?
    Absorbance = (slope of line)(Concentration)
  9. What is a centrifuge?
    A mechanical device that accelerate the rate of sedimentation by rapidly spinning and increasing centrifugal force
  10. What is the formula to calculate relative Centrifugal field? (RCF)
    RCF = 11.2 x r (RPM/1000)2
  11. What is the equation for calculating RPM from g force?
    RPM = 1000 x [RCF/ (11.17 x r)]1/2
  12. What determines the rate of sedimentation?
    • relative centrifugal field
    • Viscosity
    • Size of particles
  13. What is the sediment coefficient (S)?
    • The value that expresses the rate of sedimentation for a given particle
    • The larger the value the quicker it will sediment
  14. What materials are used to make preformed gradients?
    • Sucrose
    • Ficoll
  15. What 3 ways are centrifuges classified based on mode of operation?
    • Differential (Pellet and Supernatant)
    • Density (Separation of fluids through density gradient)
    • Continuous (large scale and supernatant is slowly discarded)
  16. What 2 methods of centrifugation is used in density gradient?
    • Rate Zonal
    • Buoyant Density
  17. What are the 3 styles of centrifuge rotors?
    • Horizontal (good for cells, takes longer)
    • Fixed Angle (sheers cells (bad), very quick though)
    • Vertical (used for buoyant density separation)
  18. What is the optimal temperature, humidity, and CO2 level for mammalian cells growth?
    • 37 degrees
    • 80-95% humidity
    • 5% CO2
  19. What percent of contaminates does the HEPA filter in the incubator remove?
  20. How is the CO2 level in the incubator monitored and controlled?
    • Ours- Thermal conductivity (TC) sensor
    • Infrared (IR) sensor
  21. What is magnification?
    The ability to enlarge the visual image of the specimen.
  22. What is resolving power?
    The power to distinguish between 2 points as distinct separate entities
  23. What is resolution?
    The limit at which two small objects can be distinguished from each other.
  24. What is oil immersion?
    A technique to maximize resolution of fixed cells
  25. What is a field of view?
    The amount of specimen that can be seen through the microscope
  26. What is working distance?
    Distances between the objective lens and the specimen
  27. What is the most commonly used microscopy imaging technique?
    Brightfield (light is passed through or reflected off a specimen)
  28. What is the difference between a TEM and SEM microscope?
    • TEM - 2D
    • SEM -3D
  29. What is pH and how is it measure?
    • Measurement of alkalinity or acidity
    • pH= -log [H+]
  30. What is an osmometer?
    A device for measuring the osmotic strength of a solution
  31. What is accuracy of a balance?
    The correctness of the measurement
  32. What is precision?
    The consistency of the instrument
  33. What is sterilization?
    Total destruction of all forms of life
Card Set
Instrumentation Final
Instrumentation Final Comprehensive