Lab 2 - Lab 2: Micropipettes, Microscopy, Pro- and...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon
Lab 2: Micropipettes, Microscopy, Pro- and Eukaryotes
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Micropipettes P20 for 1 to 20μl; P200 for 20 to 200μl: P1000 for 200 to 1000μl Always use a tip (yellow for P20 and P200: blue for P1000) Hold pipettes upright Sterile technique (keep tips covered, do not touch tips,. ..) 2 points of resistance: Plunger to 1 st point = indicated volume (take fluid in/out) Plunger to 2 nd point = dispenses reminding fluid Press/release the plunger slowly, submerge the tip just as needed Calibration using a scale: 1 g = 1000 μl = 1 ml = 10 -3 l
Background image of page 2
Microscopy 5 3 1 4 2 5 + 6 7 8 3 6 Start with low power objective! Light, field – and aperture diaphragm need adjustment for each objective!
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Critical illumination: Use the right amount of light. The light also needs to be focused on the specimen for optimal resolution and contrast. Distance of resolution (separate two points) d = 0.6 x λ / N.A. N.A. = n x sin α λ : wavelength of light (white is ~ 500nm, UV is ~400nm) N.A.: numerical aperture (found on objective) n: refraction index of medium (1 for air, 1.5 for oil) sin α : angle of light Smaller d values = higher resolution To increase resolution make the nominator ( λ ) small and/or the denominator (N.A.) big Magnification: Total magnification = magnification of ocular X magnification of objective
Background image of page 4
Field of view (parachute cloth) 100 μm 100 μm 100 x total 400 x total 250 μm 1000 μm Ruler calibration (micrometer is true at 1000x total mag!) # of increments (measuring device is in one ocular) per 100μm 100x: 400x: 10 increments in 100μm = 10μm /bar 40 increments in 100μm = 2.5μm /bar
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Magnification, Field of view, increments: Do the math in 100 μm rs field of view μm/ruler bar x factor 1 ?
Background image of page 6
Image of page 7
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 12

Lab 2 - Lab 2: Micropipettes, Microscopy, Pro- and...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online