~ Ch. 4 ~

Microscope Stuff I

100

Contrast – differences in intensity b. Energy source to magnify a. light, UV, electrons; b. the shorter the wavelength – the greater the magnification c. Total magnification – Ocular X Objective d. Resolution – ability to distinguish between two close objects a. Higher resolution at greater magnifications e. Refraction – bending of light waves and the effect on resolution (clarity) a. oil immersion- use oil to decrease refraction

What is light microscope

200

Light background with dark specimen b. Compound – uses a series of lenses for magnification c. Light passes through specimen, from underneath, into objective lens d. Total magnification (objective lens X ocular lens) e. Most have condenser lens (direct light through specimen) f. Uses a. Killed stained specimens b. Live colored organisms

What is Bright - field microscope

300

a. Increases contrast – dark background with light specimen on darkfield b. Best for observing live colorless objects c. polarized light d. Used with organisms that are difficult to stain a. Treponema pallida (causative agent of Syphilis) e. Displays the organism but is not helpful with internal anatomy.

What is Dark field microscope

400

a. Displays internal structures b. Utilizes special filter to slightly change light waver, producing more contrast

What is phase microscope

500

Direct UV light source at specimen b. Specimen radiates energy back as a visible wavelength c. UV light increases resolution and contrast d. Specific staining with immunofluorescence a. Add antibodies (with attached fluorescent dye) specific for an antigen on the surface of a microbe b. If microbe is present and antibodies attach, UV light causes organism to emit light c. If microbe is absent, you see nothing. d. Allows for the localization fo specific chemicals or structures

What is fluorescent microscope

Microscope Stuff II

100

a. Energy source is electrons – short wavelength, good resolution b. Greater resolving power and magnification c. Magnifies objects 10,000X to 100,000X d. Detailed view of bacteria, viruses, ultrastructure, and large atoms

What is electron microscope

200

i. Used to observe detail of internal structures ii. Requires cutting specimens into very thinn (100 nm thick) slices

What is transmission electron microscope

300

i. Used to observe extreme detail of the ultrastructure (surface) of an organism or sample ii. Can only observe dead organisms iii. Organism coated with a metal (palatium or gold)

What is scanning electron microscope

400

b. Uses needle like probe to map surface of a specimen c. Uses electron flow to measure the distances between probe and surface of an object d. Magnifies more than 100,000,000X (SUPER FINE DETAIL)

What is probe microscope

Gram Staining I

100

Coloring the microbe with a dye that emphasizes certain structures

What is staining

200

A thin film of a solution of microbes on a slide

What is a smear

300

this process is used to attach the microbes to the slide and to kill the microbes

What is fixation

400

these types of stains consist of a positive and negative ion so the bacteria is able to be stained

What is a basic dye

500

colored salts in stains

What is chromophore:

Gram Staining II

100

In this type of dye the chromophore is an negative ion (anion) b. Repelled by negative charge on bacterial cell c. Used in negative staining procedure a. Stains background/slide and not the bacterial cell b. Results in a dark background with clear cells

What is acidic dye

200

this can be used to: a. hold the stain b. coat the specimen to enlarge it

What is mordant

300

These types of stains can be be used to: 1. Distinguish between bacteria 2. Typically uses more than one stain common types are: gram staining and acid-fast stains

What is differential stains

400

when gram staining it is crucial to rinse this right away in order to not strip away the primary stain and mordant

What is alcohol

500

this indicates the presence of fatty acids a. For bacteria that have waxy material in cell walls b. Mycobacterium (tuberculosis and leprae) c. Nocardia

What is acid-fast stains

MISC.

100

environmentally resistant stage of some bacteria i. Produced in unfavorable growth conditions ii. Can be viewed using gram stain 1. Highly refractive 2. Usually appear as clear circle inside of stained cell 3. Though difficult to differentiate from cellular inclusions iii. The _____ itself cannot be stained by simple stains and gram stain 1. Dyes do not penetrate wall of ____________ (THINK CDIFF)

What is an endospore

200

the following are used for what purpose: 1. Shapes of bacteria – staining with microscopy 2. Reproduction – binary fission, host cell, sexual reproduction, asexual reproduction (mitosis) 3. Arrangements – staining with microscopy 4. Physical characteristics – microscopy, colony morphology etc.

What is classifying microbes

300

i. Provides protection from phagocytosis ii. Virulence factor – allows microbe to evade immune system and cause disease

What is a capsule

400

this type of stain allows the specimen to appear as colored cells with a halo around them on a dark background

What is capsule staining

500

endospore staining name

What is Schaeffer-Fulton endospore stain