Lab 2: Microscopy and Cell Structure Flashcards
where and when were the first microscopes made?
1600 in the Netherlands
who made the first compound microscope?
Galilei
Which has a smaller wavelength: electrons or visible light?
electrons
What is B?
Objective lens
What is F?
Course Focus Adjustment Knob
What is A?
Eyepiece (ocular)
What is C?
Stage
What is D?
Iris diaphragm ring
What is E?
Base
What is G?
Fine focus adjustment knob
Memorize this
Memorize
To view a specimen under an electron microscope, it has to be living.
T/f
false
What determines resolution
Visual Acuity
Lens Quality
Magnification
Lens Diameter
Ocular lenses found in most compound light microscopes a magnification of
10x
which have a higher magnification
Dissecting microscopes or compound microscopes.
compound microscpes
Produce 3-D images of the surfaces of objects.
scanning electron microscope (SEM)
You are using a compound microscope and you have the objective lens set to 40x. What is the total magnification you are using to view the specimen?
400x
If you were given a sample of bacteria to analyze, which microscope would be best for quickly identifying the specimen?
compound
use visible light to visualize small structures.
Light microscopes
High-powered compound
microscopes allow for magnification up to about what?
1000x
while dissecting microscopes allow for magnification up to what?
100x
which is the ratio of the size of the
image seen in the microscope versus the actual size of the object.
magnification
The magnification of a light microscope is limited by what?
the wavelength
, which is the ability of the microscope to resolve, or separate, two points.
resolution
the magnification achieved by electron microscopes is
much greater then 1,000,000X
inorder to visualize materials in an electron
microscope they must be what?
coated with metal ions, and this process kills living
specimens.
two types of electron microscopes
Transmission electron microscopes (TEM)
and
Scanning electron microscopes (SEM)
are conceptually analogous to compound
optical microscopes in that the beam of
electrons passes through the sample and is
then used to produce an image.
Transmission electron microscopes (TEM)
produce three-dimensional images of the surfaces
of objects
Scanning electron microscopes (SEM)
what is the relationship between magnification and field size
as one magnifies the field size gets smaller
the plane through the focus perpendicular to the axis of a mirror or lens.
focal plane
where is the focal plane limited
at higher magnification
A rapid control which allows for quick focusing by moving the objective lens or stage up and down.
coarse adjustment knob
A slow but precise control used to fine focus the image when viewing at the higher magnifications.
fine adjustment knob
