The Microscope (exercise 3)

Caring for a microscope

- hold in upright position with one hand on arm and other holding the base - use only special grit-free lens paper in circular motion. clean before and after use - always begin with the scanning objective lens - only use coarse adjustment knob with scanning objective lens - always use cover slip with wet mount preparations - before putting away remove slide, rotate to the scanning objective lens, wrap up cord

centimeter (cm)

10⁻²m

millimeter (mm)

10⁻³m

Micrometer or micron (µm)

10⁻⁶m

nanometer (nm)

10⁻⁹m

If the ocular lens magnified a specimen 10x, and the objective lens used magnifies the specimen 35x, what is the total magnification being used to observe the specimen?

350x

you should always begin observation of specimens with the oil immersion lens

TRUE

compound microscope

a precision instrument and should always be handled with care

meter (m)

about 39.37 in

depth of field (the thickness of the plane that is clearly in focus)

is greater at lower magnifications. as magnification increases, depth of field decreases

oil immersion lens

magnification of objective lens: 100x magnification of ocular lens: 10x total magnification: 1000x

low power lens

magnification of objective lens: 10x magnification of ocular lens: 10x total magnification: 100x

high power lens

magnification of objective lens: 40x magnification of ocular lens: 10x total magnification: 400x

scanning lens

magnification of objective lens: 4x magnification of ocular lens: 10x total magnification: 40x

the microscope slide rests on the ________ while being viewed

stage

resolution

the ability to discriminate two close objects as separate *determined by the amount and physical properties of the visible light that enters the microscope

Your lab microscope is parfocal. What does this mean?

the slide should be almost in focus when changing to higher magnifications

how do you clean the lenses of your microscope?

with special lens paper and cleaner