Exam 2: Microscopy

Immersion oil can be used to increase the resolution achieved with some microscope lenses because it increases the __________ between the specimen and the objective lens.

After the secondary stain has been added,gram-positive organisms are stained __________ and gram-negative organisms are stained __________.

Scanning electron microscopes bombard specimens with a stream of electrons; however,the specimen image is produce by electrons that are derived from atoms of the specimen itself rather than by the electrons used to bombard the specimen.

The designer of the first transmission electron microscope,_________________,was awarded the 1986 Nobel Prize in physics.

In order to stain flagella so that they may be readily observed by light microscopy,it is usually necessary to increase their thickness.

In the Gram-staining procedure,the counterstain is

A 45 $\times$ objective and a 10 $\times$ ocular produce a total magnification of

The Gram-staining procedure is an example of:

A substage condenser is used to focus light onto the specimen,which increases the resolution of a light microscope.

As the magnification of a series of objective lenses increases,the working distance

If the decolorizer is not left on long enough in the Gram-staining procedure,gram-positive organisms will be stained __________ and gram-negative organisms will be stained __________.

__________ breaks frozen specimens along lines of greatest weakness,often down the middle of lipid bilayer membranes so that they may be observed by transmission electron microscopy.

An instrument that magnifies slight differences in the refractive index of cell structures is called a (n)__________ microscope.

Acid-fast organisms such as Mycobacterium tuberculosis contain __________ constructed from mycolic acids in their cell walls.

Light rays are refracted (bent)when they cross the interface between materials with different refractive indices.

The useful magnification of a light microscope is limited by the ___________ of the light source being utilized.

An electron microscope uses __________ lenses to focus beams of electrons onto a specimen.

The procedure in which a single stain is used to visualize microorganisms is called __________ staining.

Scanning electron microscopy is most often used to reveal

Because transmission electron microscopy uses electrons rather than light,it is not necessary to stain biological specimens before observing them.