microscopy Flashcards
(9 cards)
when using microscopes, what two variables matter the most?
magnification , resolution
write a definition for magnification
magnification tells us how many times larger an image seen through a microscope is compared to the real object
write a definition for resolution
resolution is the ability to distinguish between two or more objects that are close together
what is the equation for magnification
magnification = magnified size of object
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real size of the object
what is a light microscope
a light microscope passes light through a specimen , and creates a magnified image using lense.
the first light microscope was made using two lenses in the late 16th century. it had a resolution better than the human eye itself
what are some discovery’s using the light microscope
light microscopes allowed bacteria to be seen for the first time , they also allowed bacteria us to see plant cells and animal cells as separate objects
however we still could not tell lots of sub cellular structures apart
what is an electron microscope
the electron microscope was first used in 1933
they work in a similar way to light microscopes however the electrons are passed within specimen not light.
they can now resolve distances of 1nm (better resolution) with magnification of x500,000
what are some discoveries that used electron microscopes
the high level of detail of electron microscopes allowed scientists to see sub cellular structures more clearly.
they also allowed scientists to study how structure such as mitochondria , chloroplasts and ribosomes function
what is the name of the lens with the lowest magnification that we use to initially focus on a sample?
objective lens
