Chapter 4: Microscopy, Staining, and Classification Flashcards
What refers to the use of light of electrons to magnify objects?
Microscopy
What is the difference between two corresponding parts of a wave.
wavelength
What is the apparent increase in size of an object called?
magnification
What are the name of the properties that determine the clarity of an image, which in turn determines the useful magnification of a microscope?
Resolution and Contrast
What is the ability to distinguish objects that are close together?
Resolution
What refers to differences in intensity between two objects or between an object and its background?
Contrast
What are the names of the two basic type of bright-field microscopes?
Simple microscopes and compound microscopes.
Which microscope contains a single magnifying lens and is more similar to a magnifying glass than to a modern microscope?
Simple microscope
What microscope uses a series of lenses for magnification?
Compound microscope
What is the name of the lens immediately above the object being magnified?
Objective
Most light microscopes have 3 or 4 objective lenses mounted on what?
A revolving nosepiece
An oil immersion lens increases not only magnification but also _____.
Resolution
Immersion oil increases the ____________, which increases resolution.
numerical aperture
The distance between the lens and the specimen is called what?
Working distance
What part of the light compound microscope remagnifies the image formed by the objective lens?
Ocular lens
What is determined by multiplying the magnification of the objective lens by the magnification of the ocular lens?
Total Magnification
What part of the light compound microscope transmits the image from the objective lens to the ocular lens using prisms?
Body
What part of the compound microscope is the primary lenses that magnifies the specimen?
Objective lenses
What part of the light compound microscope holds the microscope slide in position?
Stage
What part of the light compound microscope focuses light through specimen?
Condenser
What part of the light compound microscope controls the amount of light entering the condenser?
Diaphragm
What part of the light microscope moves the stage up and down to focus the image?
Coarse focusing knob
Name the parts of the following bright-field, compound light microscope below starting from the top:
- Ocular Lens
- Body
- Arm
- Objective lens
- Stage
- Condenser
- Diaphragm
- Illuminator
- Coarse focusing knob
- Fine focusing knob
- Base
A principle of microscopys is that resolution distance is dependent on what two things?
- The wavelength of the electromagnetic radiation
- The numerical aperture of the lens
What part of the moderm compound microscope directs light through the specimen?
Condenser lens
Pale objects are best observed by what kind of microscope?
Dark field microscopes
What do dark-field microscopes contain that prevents light from directly entering the objective lens?
Dark-field stop
The specimen in a dark field microscope appears ____ against dark background?
Light
What kind of microscopes are used to examine living microorganisms or specimens that would be damaged or altered by attaching them to slides or staining them.
Phase microscopes
Light rays are said to be in phase when their crests and troughs are ____.
aligned.
Light rays are said to be __________ when their crests and troughs are not aligned.
out of phase
Light rays in phase produce_____ image.
Brighter
Light rays out of phase produce
_________ image.
Darker
What are the two types of Phase Mircoscopes?
Phase-Contrast and Differential Interference Contrast microscope
The simplest phase mircoscope is called what?
Phase-contrast microscope
What Phase microscope produces sharply defined images in which fine structures can be seen in living cells?
Phase-contrast
What are two prokaryotic structures that phase-contrast microscopes are particularly useful for?
Cilia and flagella
What phase microscope creates phase interference patterns?
Differential interference contrast microscopes
Molecules that absorb energy from invisible radiation and then radiate the energy back as a longer, visble wavelength are said to be ___________.
Fluorescent
What type of light in fluorescnece microscopes increaes resolution?
UV light
What can be used in fluorescence microscopes for cells and cellular structures that are not natually fluorescent?
Fluorescent dyes
How can immunofluorescence be used?
to identify pathogens and to make visible a variety of proteins of interest.
What is a similarity between Confocal microscopes and Fluorescent microscopes?A difference?
- Use fluorscent dyes
- Difference: Use UV lasers to to illuminate the fluorescent chemicals in only single plane no thicker than 1. micrometer
What type of light microscopy microscope constructs 3D image from digitized images?
Confocal Microscopes
Structures that can’t be distingued using a light microscope that are closer together then about 200 nanometers use what type of microscopy?
Electron microscopy
Cellular structures that can be seen only by using electron microscopy are referred to as the cell’s _______________.
Ultrastructure
What are the two general types of electron microscopes?
- Transmission electron microscope
- Scanning eletron microscope
What type of Microscopy maginifies objects 10,000x to 100,000x
Electron microscopy
What type of microscope generates a beam of electrons that ultimately produces an image on a fluorescent screen?
Transmission Electron microscope
Can transmission electron microscopes be used to study living organisms?
No
What slicing machine is used to examine thicker specimens such as whole cells in a transmission electron microscope?
Ultramicrotome
The column of a Transmission electron microscope must be a __________.
Vacuum
What is the similarity and difference between a scanning electron microscope and a transmission?
- Similarity: use Vaccum column
- Difference: Rather than passing electrons through a specimen , the SEM rapidly focuses them back and forth across the specimen’s surface, which has previosuly been coated with a metal such as platinum or gold.
What is an advantage of SEM over TEM microscopy?
Whole species can be observed because sectioning is not required.