Exam 2: Microscopy

In the Gram-staining procedure,the mordant is

After the primary stain has been added but before the decolorizer has been used,gram-positive organisms are stained __________ and gram-negative organisms are stained __________.

A procedure that divides organisms into two or more groups depending on their individual reactions to the same staining procedure is referred to as __________ staining.

Immersion oil is used to prevent a specimen from drying out.

The Schaeffer-Fulton procedure is used to stain

In order to view a specimen with a total magnification of 400 $\times$ ,a __________ objective must be used if the ocular is 10 $\times$ .

Resolution decreases when the wavelength of the illuminating light decreases.

A light microscope with an objective lens numerical aperture of 0.65 is capable of allowing two objects 400 nm apart to be distinguished when using light with a wavelength of 420 nm.

Regions of a specimen with higher electron density scatter ___________ electrons and,therefore,appear __________ in the image projected onto the screen of a transmission electron microscope.

Gram staining divides bacterial species into roughly two equal groups.

Confocal microscopes exhibit improved contrast and resolution by

In transmission electron microscopy,spreading a specimen out in a thin film with uranyl acetate,which does not penetrate the specimen,is called

The instrument that produces a bright image of the specimen against a dark background is called a (n)__________ microscope.

A microscope that exposes specimens to ultraviolet,violet,or blue light and forms an image with the light emitted at a different wavelength is called a __________ microscope.

In the Gram-staining procedure,the decolorizer is

If the objective lenses of a microscope can be changed without losing focus on the specimen,they are said to be

The Gram-staining procedure is widely used because it allows rapid identification of a microorganism with little additional testing.

The _________________ microscope is capable of atomic resolution of specimens,even when they are immersed in water.

Thin films of bacteria that have been air-dried onto a glass microscope slide are called __________.

Atomic force microscopes use a scanning probe that maintains a fixed distance from the surface of the specimen.It is useful for specimens that