Chapter 2 Connect

Name the characteristics that describe objectives that have a short working distance.

1. Large numerical aperture 2. Great resolving power

Which chemicals are used in the staining process of specimens for the TEM? [ ] osmium tetroxide [ ] malachite green [ ] uranyl acetate [ ] crystal violet [ ] lead citrate

1. Osmium Tetroxide 2. Uranyl acetate 3. Lead citrate

The gram stain is an example of __________staining, distinguishing gram negative and gram positive.

Differential

members of the gram-positive bacterial genera bacillus and clostridium may produce highly resistant structure known as a(n) _________ in order to survive unfavorable enviornments.

Endospore

the most recognized differential staining procedure used in microbiology is known as the _______ stain.

Gram

Our eye can minimally detect something that is about 0.2 __________ in diameter.

Millimeters

India ink and nigrosin are both _______stains which stain the background and not the cell.

Negative

The lens closest to the specimen are collectively referred to as the __________ lens.

Objective

Using dark-field microscopy, a hollow cone of light is focused on the specimen so that unreflected and unrefracted rays do not enter the ________lens.

Objective

Capsules are networks composed mostly of ___________ that surround many bacteria.

Polysaccharides

TEM specimens are coated with a thin film of platinum or other heavy metal in the _________process.

Shadowing

Which statements are limitations of the light microscope? [ ] light microscopes have a resolution limit of 2 micrometers. [ ] light microscopes are not able to show the shape and arrangement of bacteria [ ] light microscopes are not able to show detailed internal cellular structure [ ] light microscopes have a resolution limit of 0.2 micrometers.

[ ] light microscopes are not able to show detailed internal cellular structure [ ] light microscopes have a resolution limit of 0.2 micrometers.

Which of the following must be done in order to prepare a specimen for SEM? [ x] dried [ x] metal coated [ x] dehydrated [ ] stained [ x] fixed

[ x] dried [ x] metal coated [ x] dehydrated [ ] stained [ x] fixed

Identify any of the following that are associated with electron microscopes: [ ] electromagnets [ ] viewing screen [ ] electron beams [ ] light rays [ ] glass lenses

[ x] electromagnets [x ] viewing screen [ x] electron beams

Which type of microscope is used in microbiology labs to examine both stained and unstained specimens? a) bright-field b) confocal c) dark-field d) phase-contrast

a) bright-field

What compound is used to stain a specimen that will emit a different wavelength of light than it absorbs? a) flurochromes b) crystal violet c) india ink d) heavy metals

a) flurochromes

Which process is used to observe organelles within cells using a TEM? a) freeze-etching b) shadowing c) negative staining

a) freeze-etching

What type of light source is used in the differential interference contrast (DIC) microscope? a) Plane-polarized light b) incadescent light c) ultraviolet light d) fluorescent light

a) plane-polarized light

When performing a stain, which two things generally occur during the fixation step? a. Cells are killed b. Cells are attached to slide c. Cells are stained d. Cells are distorted

a. Cells are killed and... b. Cells are attached to slide

The ability of the lens to gather light is called numerical __________.

aperture

What term describes when a microscope image stays focused even when changing the objective lens? a) binocular b) parfocal c) refraction d) resolution

b) parfocal

What occurs when an objective produces not just a magnified image but a clear image? a) refraction b) resolution c) parfocal d) magnification

b) resolution

Which part of the specimen scatters more electrons and therefore appears darker? a) the lease dense region b) the most dense region

b) the most dense region

Which microscope part is mounted beneath the stage to focus light on the slide? a. Objective lens b. Substage condenser c. Coarse Adjustment d. Ocular Lens

b. Substage condenser

Methylene blue, crystal violet and safranin are examples of what kind of dye? basic or acidic

basic

Which of the following describes vitreous ice? a) a compound that changes from liquid to solid states easily to help break apart cells for better viewing using microscopy. b) a plastic polymer that seals a specimen for light microscopy use? c) a glass-like solid that preserves the native state of structure for use with an electron microscope.

c) a glass-like solid that preserves the native state of structure for use with an electron microscope.

Which types of microscopes are NOT able to create clear images of living specimens? a)bright field microscope b) dark field microscope c) electron microscope d) phase-contrast microscope e) differential microscope

c) electron microscope

Ocular lenses are also known as ________. a) endpieces b) low power objective c) eyepieces d) eye residence stage (ERS)

c) eyepiece

In which process are specimens plunged into an extremely cold liquid? a) scanning probe microscopy b) immunofluorescence microscopy c) electron cryotomography d) confocal microscopy

c)Electron cryotomography

Many types of dyes used to stain microorganisms have __________ groups which are chemical moieties with conjugated double bonds that give the dye its color.

chromophore

Correctly list the steps of the gram stain crystal violet primary stain iodine, mordant acetone-alcohol, decolorizer safranin, counterstain

crystal violet primary stain iodine, mordant acetone-alcohol, decolorizer safranin, counterstain

In negative staining of TEM specimens, the ______appears dark. a) cell membranes b) cell c) nucleus d) background

d) background

In epifluorescent microscopes, what do objective lenses act as so the specimen is illuminated from above rather than below? a) course adjustment b) ocular lens c) light source d) condenser

d) condenser

What type of microscopes are often used to study biofilms? a) fluorescent b) bright-field c) phase-contrast d) confocal

d) confocal

In fluorescent microscopy, the _____ absorbs light energy from the excitation light and fluoresces brightly. a) antibody b) glass slide c) cover slip d) fluorochrome

d) fluorochrome

Identify any of the following that are associated with light microscopes: [ ] eye [ ] viewing screen [ ] lamp [ ] electron gun [ ] glass lenses

eye lamp glass lenses

The use of __________ oil when viewing a slide prevents the refraction of light and allows the viewer to see the image much clearer.

immersion

In the acid-fast staining process, non-acid-fast cells are decolorized by acid-alcohol removing the basic fuchsin, and are then counterstained with ___________ blue.

methylene

Acid-fast organims have lipids constructed of _______ acid in their cell walls.

mycolic

Known for ease of use, __________ staining only uses one stain.

simple

In the flagella stain, the thickness of the flagella is increased by coating them with mordants such as ________ acid and potassium alum.

tannic

The ocular and objective magnification must be multiplied to determine the _____________ magnification.

total

What type of cells are difficult to view in a bright-field microscope? pigmented unpigmented

unpigmented