The method for doing this is called K\u00f6hler illumination Results in an evenly

The method for doing this is called köhler

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The method for doing this is called Köhler illumination. Results in an evenly illuminated field and a bright image without glare. Achieved by adjusting the height of the condenser (and closing the field diaphragm): Watch this video !
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Condenser Knob moves the condenser up or down to control the lighting focus on the specimen. Field Diaphragm Controls the diameter of the light beam before it enters the condenser aperture Focus specimen. Close field diaphragm. Adjust height of condenser until leaves of the field diaphragm are in sharp focus. Use the condenser centering screws to move the image of the field diaphragm to the center. Open field diaphragm. Setting Köhler
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2.4, 2.5, 2.6 Measuring size The ocular reticle is found in the ocular and is a arbitrary ruler that can be used to measure objects. Must first be calibrated with a stage micrometer . Must do this for each objective . Watch these videos: https :// https://
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Reticle Units Let’s say that you determine there are 40 reticle units per millimeter. How many µm are there per r.u.? Remember that 1000 µm = 1 mm So there are 40 r.u. per 1000 µm. So 1 r.u. = 25 µm
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For a particular microscope one reticle unit represents 25 µm when using the 4X objective. You want to know the number of µm’s per r.u. when using the 40X objective on the same microscope. An equation: µm/r.u. x (Mag. of original objective /Mag. of new objective) = µm/r.u. a. 250 µm b. 25µm c. 2.5 µm d. .25 µm
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Paramecia (protist) and Elodea (plant) What do you know about the structure and function of these types of organisms? What might they have in common? What are their differences?
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2.7 Living Specimens (Fun!) In this section you will learn how to prepare a wet mount slide and study the structure and function of these organisms (and others) Watch this video : https:// Make sure to use your notebook for observations. You’ll examine a variety of specimens including: Living Paramecia :
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  • Spring '08
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  • Biology

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